Hydroxy-biphenyl-carbaldehyde oxime derivatives and their use as estrogenic agents

ABSTRACT

This invention provides estrogen receptor modulators having the structure:  
                 
 
wherein R 1  to R 6  and R 8  are as defined in the specification; or a pharmaceutically acceptable salt thereof.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims benefit to U.S. Provisional Application Ser. No. 60/467,394, filed May 2, 2003, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

This invention relates to novel 4′-hydroxy-biphenyl-carbaldehyde oxime derivatives, their uses as estrogenic agents, and methods of their preparation.

BACKGROUND OF THE INVENTION

The pleiotropic effects of estrogens in mammalian tissues have been well documented, and it is now appreciated that estrogens affect many organ systems [Mendelsohn and Karas, New England Journal of Medicine 340: 1801-1811 (1999), Epperson, et al., Psychosomatic Medicine 61: 676-697 (1999), Crandall, Journal of Womens Health & Gender Based Medicine 8: 1155-1166 (1999), Monk and Brodaty, Dementia & Geriatric Cognitive Disorders 11: 1-10 (2000), Hum and Macrae, Journal of Cerebral Blood Flow & Metabolism 20: 631-652 (2000), Calvin, Maturitas 34: 195-210 (2000), Finking, et al., Zeitschrift fur Kardiologie 89: 442-453 (2000), Brincat, Maturitas 35: 107-117 (2000), Al-Azzawi, Postgraduate Medical Journal 77: 292-304 (2001)]. Estrogens can exert effects on tissues in several ways. Probably, the most well characterized mechanism of action is their interaction with estrogen receptors leading to alterations in gene transcription. Estrogen receptors are ligand-activated transcription factors and belong to the nuclear hormone receptor superfamily. Other members of this family include the progesterone, androgen, glucocorticoid and mineralocorticoid receptors. Upon binding ligand, these receptors dimerize and can activate gene transcription either by directly binding to specific sequences on DNA (known as response elements) or by interacting with other transcription factors (such as AP1), which in turn bind directly to specific DNA sequences [Moggs and Orphanides, EMBO Reports 2: 775-781 (2001), Hall, et al., Journal of Biological Chemistry 276: 36869-36872 (2001), McDonnell, Principles Of Molecular Regulation. p351-361(2000)]. A class of “coregulatory” proteins can also interact with the ligand-bound receptor and further modulate its transcriptional activity [McKenna, et al., Endocrine Reviews 20: 321-344 (1999)]. It has also been shown that estrogen receptors can suppress NFκB-mediated transcription in both a ligand-dependent and independent manner [Quaedackers, et al., Endocrinology 142: 1156-1166 (2001), Bhat, et al., Journal of Steroid Biochemistry & Molecular Biology 67: 233-240 (1998), Pelzer, et al., Biochemical & Biophysical Research Communications 286: 1153-7 (2001)].

Estrogen receptors can also be activated by phosphorylation. This phosphorylation is mediated by growth factors such as EGF and causes changes in gene transcription in the absence of ligand [Moggs and Orphanides, EMBO Reports 2: 775-781 (2001), Hall, et al., Journal of Biological Chemistry 276: 36869-36872 (2001)].

A less well-characterized means by which estrogens can affect cells is through a so-called membrane receptor. The existence of such a receptor is controversial, but it has been well documented that estrogens can elicit very rapid non-genomic responses from cells. The molecular entity responsible for transducing these effects has not been definitively isolated, but there is evidence to suggest it is at least related to the nuclear forms of the estrogen receptors [Levin, Journal of Applied Physiology 91: 1860-1867 (2001), Levin, Trends in Endocrinology & Metabolism 10: 374-377 (1999)].

Two estrogen receptors have been discovered to date. The first estrogen receptor was cloned about 15 years ago and is now referred to as ERβ [Green, et al., Nature 320: 134-9 (1986)]. The second was found comparatively recently and is called ERβ [Kuiper, et al., Proceedings of the National Academy of Sciences of the United States of America 93: 5925-5930 (1996)]. Early work on ERβ focused on defining its affinity for a variety of ligands and, indeed, some differences with ERα were seen. The tissue distribution of ERα has been well mapped in the rodent and it is not coincident with ERα. Tissues such as the mouse and rat uterus express predominantly ERα, whereas the mouse and rat lung express predominantly ERβ [Couse, et al., Endocrinology 138: 4613-4621 (1997), Kuiper, et al., Endocrinology 138: 863-870 (1997)]. Even within the same organ, the distribution of ERα and ERβ can be compartmentalized. For example, in the mouse ovary, ERβ is highly expressed in the granulosa cells and ERα is restricted to the thecal and stromal cells [Sar and Welsch, Endocrinology 140: 963-971 (1999), Fitzpatrick, et al., Endocrinology 140: 2581-2591 (1999)]. However, there are examples where the receptors are coexpressed and there is evidence from in vitro studies that ERα and ERβ can form heterodimers [Cowley, et al., Journal of Biological Chemistry 272: 19858-19862 (1997)].

The most potent endogenous estrogen is 17β-estradiol. A large number of compounds have been described that either mimic or block the activity of 17β-estradiol. Compounds having roughly the same biological effects as 17β-estradiol are referred to as “estrogen receptor agonists”. Those which block the effects of 17β-estradiol, when given in combination with it, are called “estrogen receptor antagonists”. In reality, there is a continuum between estrogen receptor agonist and estrogen receptor antagonist activity and some compounds behave as estrogen receptor agonists in some tissues but estrogen receptor antagonists in others. These compounds with mixed activity are called selective estrogen receptor modulators (SERMS) and are therapeutically useful agents (e.g. EVISTA) [McDonnell, Journal of the Society for Gynecologic Investigation 7: S10-S15 (2000), Goldstein, et al., Human Reproduction Update 6: 212-224 (2000)]. The precise reason why the same compound can have cell-specific effects has not been elucidated, but the differences in receptor conformation and/or in the milieu of coregulatory proteins have been suggested.

It has been known for some time that estrogen receptors adopt different conformations when binding ligands. However, the consequence and subtlety of these changes only recently has been revealed. The three dimensional structures of ERα and ERβ have been solved by co-crystallization with various ligands and clearly show the repositioning of helix 12 in the presence of an estrogen receptor antagonist, which sterically hinders the protein sequences required for receptor-coregulatory protein interaction [Pike, et al., Embo 18: 4608-4618 (1999), Shiau, et al., Cell 95: 927-937 (1998)]. In addition, the technique of phage display has been used to identify peptides that interact with estrogen receptors in the presence of different ligands [Paige, et al., Proceedings of the National Academy of Sciences of the United States of America 96: 3999-4004 (1999)]. For example, a peptide was identified that distinguished between ERα bound to the full estrogen receptor agonists 17β-estradiol and diethylstilbesterol. A different peptide was shown to distinguish between clomiphene bound to ERα and ERβ. These data indicate that each ligand potentially places the receptor in a unique and unpredictable conformation that is likely to have distinct biological activities.

As mentioned above, estrogens affect a panoply of biological processes. In addition, where gender differences have been described (e.g. disease frequencies, responses to challenge, etc), it is possible that the explanation involves the difference in estrogen levels between males and females.

SUMMARY OF THE INVENTION

The present invention relates to a compound of the formula:

where

-   -   R¹ and R², are each, independently, H, halogen, CN, phenyl, or         lower alkyl;     -   R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN,         phenyl, lower alkyl, or lower alkoxy;     -   R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and     -   R⁹ is lower alkyl;     -   or a pharmaceutically acceptable salt thereof or a prodrug         thereof. In one preferred embodiment, R⁸ is H.

In another aspect, the invention relates to a compound of the formula:

In yet another aspect, the invention is directed to a compound of the formula:

In a further aspect, the invention is drawn to a compound of the formula

where R¹ is OH or lower alkoxy; and R⁵, R⁶, and R⁷ are each, independently, H, OH, halogen, CN, phenyl, lower alkyl, lower alkoxy, said phenyl, lower alkyl, and lower alkoxy being optionally substituted; or a pharmaceutically acceptable salt thereof or a prodrug thereof.

In another aspect, the invention is drawn to a pharmaceutical composition that comprises one or more of compound of the invention and a pharmaceutically acceptable carrier.

In yet other aspects, the invention is directed to use of the compounds of the invention in the treatment or prevention of diseases such as inflammatory bowel diseases.

DETAILED DESCRIPTION OF THE INVENTION

This invention provides novel 4′-hydroxy-biphenyl-carbaldehyde oxime derivatives. These compounds, which preferably act as estrogenic agents, are useful for the treatment and prevention of diseases such as inflammatory bowel diseases (including Crohn's disease and colitis). In one aspect, the invention is directed to compounds of the formula:

where

-   -   R¹ and R², are each, independently, H, halogen, CN, phenyl, or         lower alkyl;     -   R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN,         phenyl, lower alkyl, or lower alkoxy;     -   R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and     -   R⁹ is lower alkyl;     -   or a pharmaceutically acceptable salt thereof or a prodrug         thereof. In one preferred embodiment, R⁸ is H.

Compounds according to the invention can be:

In certain aspects, R³, R⁵, and R⁶ are each independently H, Cl, F, methyl, or methoxy and R² is H, Cl, F, or methyl. In another aspect, the invention is directed to compounds of the formula:

In certain aspects, R³, R⁵, and R⁶ are each independently H, Cl, F, methyl, or methoxy and R² is H, Cl, F, or methyl.

In yet another aspect, the invention is drawn to compounds of the formula

where R¹ is OH or lower alkoxy; and R⁵, R⁶, and R⁷ are each, independently, H, OH, halogen, CN, phenyl, lower alkyl, lower alkoxy; or a pharmaceutically acceptable salt thereof or a prodrug thereof. In certain embodiments, R⁵, R⁶, and R⁷ are each, independently, H, Me, Cl, F, or methoxy.

Pharmaceutically acceptable salts can be formed from organic and inorganic acids, for example, acetic, propionic, lactic, citric, tartaric, succinic, fumaric, maleic, malonic, mandelic, malic, phthalic, hydrochloric, hydrobromic, phosphoric, nitric, sulfuric, methanesulfonic, napthalenesulfonic, benzenesulfonic, toluenesulfonic, camphorsulfonic, and similarly known acceptable aids when a compound of this invention contains a basic moiety. Salts may also be formed from organic and inorganic bases, such as alkali metal salts (for example, sodium, lithium, or potassium) alkaline earth metal salts, ammonium salts, alkylammonium salts containing 1-6 carbon atoms or dialkylammonium salts containing 1-6 carbon atoms in each alkyl group, and trialkylammonium salts containing 1-6 carbon atoms in each alkyl group, when a compound of this invention contains an acidic moiety.

The term “alkyl”, as used herein, whether used alone or as part of another group, refers to a substituted or unsubstituted aliphatic hydrocarbon chain and includes, but is not limited to, straight and branched chains containing from 1 to 12 carbon atoms, preferably 1 to 6 carbon atoms, unless explicitly specified otherwise. For example, methyl, ethyl, propyl, isopropyl, butyl, i-butyl and t-butyl are encompassed by the term “alkyl.” Specifically included within the definition of “alkyl” are those aliphatic hydrocarbon chains that are optionally substituted.

The carbon number as used in the definitions herein refers to carbon backbone and carbon branching, but does not include carbon atoms of the substituents, such as alkoxy substitutions and the like.

The term “alkenyl”, as used herein, whether used alone or as part of another group, refers to a substituted or unsubstituted aliphatic hydrocarbon chain and includes, but is not limited to, straight and branched chains having 2 to 8 carbon atoms and containing at least one double bond. Preferably, the alkenyl moiety has 1 or 2 double bonds. Such alkenyl moieties may exist in the E or Z conformations and the compounds of this invention include both conformations. Specifically included within the definition of “alkenyl” are those aliphatic hydrocarbon chains that are optionally substituted. Heteroatoms, such as O, S or N—R₁, attached to an alkenyl should not be attached to a carbon atom that is bonded to a double bond.

The term “phenyl”, as used herein, whether used alone or as part of another group, referes to a substituted or unsubstituted phenyl group.

An optionally substituted alkyl, alkenyl, and phenyl may be substituted with one or more substituents. Suitable optionally substituents may be selected independently from nitro, cyano, —N(R₁₁)(R₁₂), halo, hydroxy, carboxy, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, heteroaryloxy, alkylalkoxy, alkoxycarbonyl, alkoxyalkoxy, perfluoroalkyl, perfluoroalkoxy, arylalkyl, alkylaryl, hydroxyalkyl, alkoxyalkyl, alkylthio, —S(O)₂—N(R₁₁)(R₁₂), —C(═O)—N(R₁₁)(R₁₂), (R₁₁)(R₁₂)N-alkyl, (R₁₁)(R₁₂)N-alkoxyalkyl, (R₁₁)(R₁₂)N-alkylaryloxyalkyl, —S(O)_(s)-aryl (where s=0-2) or —S(O)_(s)-heteroaryl (where s=0-2). In certain embodiments of the invention, preferred substitutents for alkyl, alkenyl, alkynyl and cycloalkyl include nitro, cyano, —N(R₁₁)(R₁₂), halo, hydroxyl, aryl, heteroaryl, alkoxy, alkoxyalkyl, and alkoxycarbonyl. In certain embodiments of the invention, preferred substituents for aryl and heteroaryl include —N(R₁₁)(R₁₂), alkyl, halo, perfluoroalkyl, perfluoroalkoxy, arylalkyl and alkylaryl.

When alkyl or alkenyl moieties are substituted, for example, they may typically be mono-, di-, tri- or persubstituted. Examples for a halogen substituent include 1-bromo vinyl, 1-fluoro vinyl, 1,2-difluoro vinyl, 2,2-difluorovinyl, 1,2,2-trifluorovinyl, 1,2-dibromo ethane, 1,2-difluoro ethane, 1-fluoro-2-bromo ethane, CF₂CF₃, CF₂CF₂CF₃, and the like.

The term halogen includes bromine, chlorine, fluorine, and iodine.

The term “lower alkyl” refers to an alkyl group having 1 to 6 carbon atoms, in some embodiments 1 to 3 carbon atoms are preferred.

The term “lower alkoxy,” as used herein, refers to the group R—O— where R is an alkyl group of 1 to 6 carbon atoms, in some embodiments 1 to 3 carbon atoms are preferred.

As used in accordance with this invention, the term “providing,” with respect to providing a compound or substance covered by this invention, means either directly administering such a compound or substance, or administering a prodrug, derivative, or analog which will form the equivalent amount of the compound or substance within the body.

The compounds of this invention can be used as estrogen receptor modulators useful in the treatment or inhibition of conditions, disorders, or disease states that are at least partially mediated by an estrogen deficiency or excess, or which may be treated or inhibited through the use of an estrogenic agent. The compounds of this invention are particularly useful in treating a peri-menopausal, menopausal, or postmenopausal patient in which the levels of endogenous estrogens produced are greatly diminished. Menopause is generally defined as the last natural menstrual period and is characterized by the cessation of ovarian function, leading to the substantial diminution of circulating estrogen in the bloodstream. As used herein, menopause also includes conditions of decreased estrogen production that may be surgically, chemically, or be caused by a disease state which leads to premature diminution or cessation of ovarian function.

Accordingly, the compounds of this invention are useful in treating or inhbiting osteoporosis and in the inhibition of bone demineralization, which may result from an imbalance in a individual's formation of new bone tissues and the resorption of older tissues, leading to a net loss of bone. Such bone depletion results in a range of individuals, particularly in post-menopausal women, women who have undergone bilateral oophorectomy, those receiving or who have received extended corticosteroid therapies, those experiencing gonadal dysgenesis, and those suffering from Cushing's syndrome. Special needs for bone, including teeth and oral bone, replacement can also be addressed using these compounds in individuals with bone fractures, defective bone structures, and those receiving bone-related surgeries and/or the implantation of prosthesis. In addition to those problems described above, these compounds can be used in treatment or inhibition for osteoarthritis, hypocalcemia, hypercalcemia, Paget's disease, osteomalacia, osteohalisteresis, multiple myeloma and other forms of cancer having deleterious effects on bone tissues.

The compounds of this invention are also useful in treating or inhibiting benign or malignant abnormal tissue growth, including prostatic hypertrophy, uterine leiomyomas, breast cancer, endometriosis, endometrial cancer, polycystic ovary syndrome, endometrial polyps, benign breast disease, adenomyosis, ovarian cancer, melanoma, prostrate cancer, cancers of the colon, CNS cancers, such as glioma or astioblastomia.

The compounds of this invention are cardioprotective and they are useful in in lowering cholesterol, triglycerides, Lp(a), and LDL levels; inhibiting or treating hypercholesteremia; hyperlipidemia; cardiovascular disease; atherosclerosis; peripheral vascular disease; restenosis, and vasospasm; and inhibiting vascular wall damage from cellular events leading toward immune mediated vascular damage. These cardiovascular protective properties are of great importance when treating postmenopausal patients with estrogens to inhibit osteoporosis and in the male when estrogen therapy is indicated.

The compounds of this invention are also antioxidants, and are therefore useful in treating or inhibiting free radical induced disease states. Specific situations in which antioxidant therapy is indicated to be warranted are with cancers, central nervous system disorders, Alzheimer's disease, bone disease, aging, inflammatory disorders, peripheral vascular disease, rheumatoid arthritis, autoimmune diseases, respiratory distress, emphysema, prevention of reperfusion injury, viral hepatitis, chronic active hepatitis, tuberculosis, psoriasis, systemic lupus erythematosus, adult respiratory distress syndrome, central nervous system trauma and stroke.

The compounds of this invention are also useful in providing cognition enhancement, and in treating or inhibiting senile dementias, Alzheimer's disease, cognitive decline, neurodegenerative disorders, providing neuroprotection or cognition enhancement.

The compounds of this invention are also useful in treating or inhibiting inflammatory bowel disease, ulcerative proctitis, Crohn's disease, and colitis; menopausal related conditions, such as vasomotor symptoms including hot flushes, vaginal or vulvar atrophy, atrophic vaginitis, vaginal dryness, pruritus, dyspareunia, dysuria, frequent urination, urinary incontinence, urinary tract infections, vasomotor symptoms, including hot flushes, myalgia, arthralgia, insomnia, irritability, and the like; male pattern baldness; skin atrophy; acne; type II diabetes; dysfunctional uterine bleeding; and infertility.

The compounds of this invention are useful in disease states where amenorrhea is advantageous, such as leukemia, endometrial ablations, chronic renal or hepatic disease or coagulation diseases or disorders.

The compounds of this invention can be used as a contraceptive agent, particularly when combined with a progestin.

When administered for the treatment or inhibition of a particular disease state or disorder, it is understood that the effective dosage may vary depending upon the particular compound utilized, the mode of administration, the condition, and severity thereof, of the condition being treated, as well as the various physical factors related to the individual being treated. Effective administration of the compounds of this invention may be given at an oral dose of from about 0.1 mg/day to about 1,000 mg/day. Preferably, administration will be from about 10 mg/day to about 600 mg/day, more preferably from about 50 mg/day to about 600 mg/day, in a single dose or in two or more divided doses. The projected daily dosages are expected to vary with route of administration.

Such doses may be administered in any manner useful in directing the active compounds herein to the recipient's bloodstream, including orally, via implants, parenterally (including intravenous, intraperitoneal and subcutaneous injections), rectally, intranasally, vaginally, and transdermally.

Oral formulations containing the active compounds of this invention may comprise any conventionally used oral forms, including tablets, capsules, buccal forms, troches, lozenges and oral liquids, suspensions or solutions. Capsules may contain mixtures of the active compound(s) with inert fillers and/or diluents such as the pharmaceutically acceptable starches (e.g. corn, potato or tapioca starch), sugars, artificial sweetening agents, powdered celluloses, such as crystalline and microcrystalline celluloses, flours, gelatins, gums, etc. Useful tablet formulations may be made by conventional compression, wet granulation or dry granulation methods and utilize pharmaceutically acceptable diluents, binding agents, lubricants, disintegrants, surface modifying agents (including surfactants), suspending or stabilizing agents, including, but not limited to, magnesium stearate, stearic acid, talc, sodium lauryl sulfate, microcrystalline cellulose, carboxymethylcellulose calcium, polyvinylpyrrolidone, gelatin, alginic acid, acacia gum, xanthan gum, sodium citrate, complex silicates, calcium carbonate, glycine, dextrin, sucrose, sorbitol, dicalcium phosphate, calcium sulfate, lactose, kaolin, mannitol, sodium chloride, talc, dry starches and powdered sugar. Preferred surface modifying agents include nonionic and anionic surface modifying agents. Representative examples of surface modifying agents include, but are not limited to, poloxamer 188, benzalkonium chloride, calcium stearate, cetostearl alcohol, cetomacrogol emulsifying wax, sorbitan esters, colloidol silicon dioxide, phosphates, sodium dodecylsulfate, magnesium aluminum silicate, and triethanolamine. Oral formulations herein may utilize standard delay or time release formulations to alter the absorption of the active compound(s). The oral formulation may also consist of administering the active ingredient in water or a fruit juice, containing appropriate solubilizers or emulsifiers as needed.

In some cases it may be desirable to administer the compounds directly to the airways in the form of an aerosol.

The compounds of this invention may also be administered parenterally or intraperitoneally. Solutions or suspensions of these active compounds as a free base or pharmacologically acceptable salt can be prepared in water suitably mixed with a surfactant such as hydroxy-propylcellulose. Dispersions can also be prepared in glycerol, liquid polyethylene glycols and mixtures thereof in oils. Under ordinary conditions of storage and use, these preparation contain a preservative to prevent the growth of microorganisms.

The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (e.g., glycerol, propylene glycol and liquid polyethylene glycol), suitable mixtures thereof, and vegetable oils.

For the purposes of this disclosure, transdermal administrations are understood to include all administrations across the surface of the body and the inner linings of bodily passages including epithelial and mucosal tissues. Such administrations may be carried out using the present compounds, or pharmaceutically acceptable salts thereof, in lotions, creams, foams, patches, suspensions, solutions, and suppositories (rectal and vaginal).

Transdermal administration may be accomplished through the use of a transdermal patch containing the active compound and a carrier that is inert to the active compound, is non toxic to the skin, and allows delivery of the agent for systemic absorption into the blood stream via the skin. The carrier may take any number of forms such as creams and ointments, pastes, gels, and occlusive devices. The creams and ointments may be viscous liquid or semisolid emulsions of either the oil-in-water or water-in-oil type. Pastes comprised of absorptive powders dispersed in petroleum or hydrophilic petroleum containing the active ingredient may also be suitable. A variety of occlusive devices may be used to release the active ingredient into the blood stream such as a semi-permeable membrane covering a reservoir containing the active ingredient with or without a carrier, or a matrix containing the active ingredient. Other occlusive devices are known in the literature.

Suppository formulations may be made from traditional materials, including cocoa butter, with or without the addition of waxes to alter the suppository's melting point, and glycerin. Water soluble suppository bases, such as polyethylene glycols of various molecular weights, may also be used.

The reagents used in the preparation of the compounds of this invention can be either commercially obtained or can be prepared by standard procedures described in the literature.

The preparation of several representative examples of this invention are described in the following Schemes 1-11.

EXAMPLE 1 4-tert-Butyl-dimethylsilyoxyphenylboronic acid

Method A. To a solution of (4-bromo-phenoxy)-tert-butyl-dimethylsilane (20 mL, 23.48g, 0.082 moles) in tetrahydrofuran (200 mL) at −78° C. was slowly added n-butyl lithium (39.2 mL of 2.5 M solution in hexane, 0.098 moles) under N₂ with stirring over a few minutes. The solution was stirred for 1 hour and triisopropyl borate (66.2 mL, 54.0g, 0.29 moles) was added by syringe at −78° C. The solution was stirred for 1 hr at −78° C. and then allowed to warm to room temperature overnight. The reaction was cooled to 0° C. and water (20 mL) and 2 N HCl (20 mL) were added into the reaction mixture. Then the whole mixture was stirred with of 2 N HCl (360 mL) for 10 minutes. The mixture was extracted with ethyl acetate (3×250 mL). The combined organic layers were concentrated to a volume of about 50 mL. Crystallization was induced with cold hexane, and the solid product was collected by filtration and dried under vacuum to yield 14.5g (70%) of the title compound as a white solid: ¹H NMR (DMSO-d₆): δ 0.19 (6H, s), 0.94 (9H, s), 6.80 (2H, d, J=8.4 Hz), 7.69 (2H, d, J=8.36 Hz), 7.87 (2H, s).

EXAMPLE 2 4′-Hydroxy-3-methyl[1,1′-biphenyl]-4-carbonitrile

Method B. A mixture of 4-bromo-2-methylbenzonitrile (1.8g, 9.18 mmol), 4-tert-butyl-dimethylsilyoxyphenylboronic acid (3.0g, 11.9 mmol), sodium carbonate (13.8 mL of 2 M aqueous solution, 27.5 mmol), tetrakis(triphenylphosphine)palladium (0.53g, 0.46 mmol), and ethylene glycol dimethyl ether (70 mL) were heated to reflux overnight. The mixture was cooled to room temperature and poured into water, then extracted with ethyl acetate (3×), washed with brine, dried over sodium sulfate, filtered, and the solvent evaporated. Purification by silica chromatography (15%-25% ethyl acetate-hexane) to yield 1.81g (94%) of the title compound as a yellowish solid: mp 177-178° C.; ¹H NMR (DMSO-d₆): δ 2.52 (3H, s), 6.88 (2H, d, J=8.50 Hz), 7.6 (3H, d, J=8.49 Hz), 7.71 (1H, s), 7.77 (2H, d, J=8.12 Hz), 9.79 (1H, s); IR 2220 cm⁻¹; MS (ESI) m/z 208 (M−H)⁻.

Anal. for C₁₄H₁₁NO:

Calc'd: C: 80.36, H: 5.30, N: 6.69

Found: C: 79.91, H: 5.27, N: 6.57.

EXAMPLE 3 4′-Hydroxy-3-methyl[1,1′-biphenyl]-4-carbaldehyde

A solution of 4′-hydroxy-3-methyl[1,1′-biphenyl]-4-carbonitrile (500 mg, 2.39 mmol) in dry toluene was cooled to −78° C. and diisobutylaluminum hydride (4.0 mL of 1.5 M solution in toluene, 5.98 mmol) was added all at once. The reaction mixture was allowed to warm to room temperature over a period of 3.5 h. Methanol (1.2 mL) was added followed by water (1.2 mL) at 0° C. and the mixture was stirred at room temperature for 20 min. 1 N HCl solution was added with stirring until pH<7. The mixture was extracted with ethyl acetate (3×), washed with brine, dried over sodium sulfate, filtered, and the solvent evaporated. Purification by silica chromatography (15%-25% ethyl acetate-hexane) to yield 459 mg (91%) of the title compound as a white solid: mp 161-162° C.; ¹H NMR (DMSO-d₆): δ 2.67 (3H, s), 6.88 (2H, d, J=8.41 Hz),

7.59-7.65 (4H, m), 7.85 (1H,d, J=8.03 Hz), 9.78 (1H, s), 10.22 (1H, s); IR 1680 cm⁻¹; MS (ESI) m/z 211 (M−H)⁻.

Anal. for C₁₄H₁₂O₂:

Calc'd: C: 79.23, H: 5.70

Found: C: 78.79, H: 5.90.

EXAMPLE 4 4′-{[tert-Butyl(dimethyl)silyl]oxy}-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting 4-bromobenzaldehyde (730 mg, 3.97 mmol) with 4-tert-butyl-dimethylsilyoxyphenylboronic acid (1.3g, 5.16 mmol) according to Method B to yield 600 mg (48%) of white crystal: ¹H NMR (DMSO-d₆): δ 0.24 (6H, s), 1.01 (9H, s), 6.94 (2H, d, J=8.54 Hz), 7.53 (2H, d, J=8.56 Hz), 7.72 (2H, d, J=8.19 Hz), 7.93 (2H, d, 8.20 Hz), 10.04 (1H, s).

EXAMPLE 5 4′-Hydroxy[1,1′-biphenyl]-4-carbaldehyde

A mixture of 4′-{[tert-butyl(dimethyl)silyl]oxy}-1,1′-biphenyl-4-carbaldehyde (320 mg, 1.03 mmol), anhydrous KF (120 mg, 2.06 mmol) and 48% aqueous HBr (35 ul, 0.31 mmol) in 6 mL dry DMF was stirred at room temperature under N₂ for 1 h. TLC indicated starting material present and therefore more 48% aqueous HBr (35 uL, 0.31 mmol) was added into the reaction and the mixture was continued to stir for 1.5 h. The mixture was then poured, with cooling, into 1 N aqueous HCl (30 mL). The aqueous mixture was extracted with EtOAc (3×). The combined extracts were washed with saturated NaCl solution, and dried over Na₂SO₄. The solvent was evaporated under reduced pressure and the product (100%) which was used directly in the next step. ¹H NMR (DMSO-d₆): δ 6.89 (2H, d, J=8.43 Hz), 7.63 (2H, d, J=8.46 Hz), 7.83 (2H, d, J=8.16 Hz), 7.94 (2H, d, J=8.02 Hz), 9.79 (1H, s), 10.01 (1H, s).

EXAMPLE 6 Trifluoro-methanesulfonic acid 3-chloro-4-formyl-phenyl ester

Method D. To a solution of 2-chloro-4-hydroxy benzaldehyde (1.31g, 8.4 mmol) and pyridine (1.1 mL, 13.4 mmol) in 80 mL of dichloromethane at 0° C. was added trifluoromethanesulfonic anhydride (1.84 mL, 3.08g, 10.9 mmol). The solution was allowed to slowly warm to room temperature and stirred for 2.5 h. The solution was cooled to 0° C. and stirred with ice water to decompose any excess anhydride. The mixture was made slightly basic by the addition of saturated sodium bicarbonate solution. The resulting layers were separated and the aqueous layer was extracted with dichloromethane (3×100 mL). The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and the solvent removed under vacuum to afford a orange oil which was purified by silica chromatography (5% ethyl acetate-hexanes) to yield 1.83g (76%) of the title compound as a clear, colorless oil: ¹H NMR (DMSO-d₆) δ 7.73 (1H, dd, J=2.35 Hz, J=8.64 Hz), 8.04-8.07 (2H, m), 10.30 (1H,s).

EXAMPLE 7 Trifluoro-methanesulfonic acid 2-fluoro-4-formyl-phenyl ester

The title compound was prepared by reacting 3-fluoro-4-hydroxybenzaldehyde (1.2g, 8.56 mmol) with trifluoromethanesulfonic anhydride (1.87 mL, 3.14g, 11.1 mmol) according to Method D to yield a yellow oil which was used directly in the next step without purification: ¹H NMR (CDCl₃): δ 7.53-7.58 (1H, m), 7.77-7.85 (2H, m), 10.01 (1H, d, J=1.45 Hz).

EXAMPLE 8 4′-{[Tert-butyl(dimethyl)silyl]oxy}-3-chloro-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 3-chloro-4-formyl-phenyl ester (1.78g, 6.18 mmol) with 4-tert-butyl-dimethylsilyoxyphenylboronic acid (2.03g, 8.03 mmol) according to Method B to yield 0.92g (43%) of white solid: mp 38-39° C.; ¹H NMR (DMDO-d₆); δ 0.23 (6H, s), 0.97 (9H, s), 6.98 (2H, d, J=8.79 Hz), 7.74 (2H, d, J=8.79 Hz), 7.81 (1H, d, J=7.81 Hz),

7.89 (1H, d, J=1.95 Hz), 7.91 (1H, d, J=7.81 Hz), 10.34 (1H, s); MS (ESI) m/z 231/233 (M−H)⁻(deprotected product ion).

Anal. for C₁₉H₂₃ClO₂Si:

Calc'd: C: 65.78, H: 6.68

Found: C: 65.59, H: 6.60.

EXAMPLES 9 and 10

Trifluoro-methanesulfonic acid 2-fluoro-4-formyl-phenyl ester (2.1g, 7.72 mmol) were reacted with 4-tert-butyl-dimethylsilyoxyphenylboronic acid (2.14g, 8.49 mmol) according to Method B to produce the following two compounds:

4′-{[tert-butyl(dimethyl)silyl]oxy}-2-fluoro-1,1′-biphenyl-4-carbaldehyde

1.62g (63%) of waxy yellowish solid: ¹H NMR (Acetone-d₆): δ 0.28 (6H, s), 1.02 (9H, s), 7.02-7.06 (2H, m), 7.57-7.60 (2H, m), 7.71-7.78 (2H, m), 7.85 (1H, dd, J=7.91 Hz, J=1.51 Hz), 10.07 (1H, d, J=1.73 Hz); ¹³C NMR (Acetone-d₆): δ−4.29, 18.80, 26.00, 116.82 (d, J=23.90 Hz), 121.15, 126.69 (d, J=3.25 Hz), 128.42 (d, 1.21 Hz), 131.30 (d, J=3.48 Hz), 132.20 (d, J=3.44 Hz), 135.27 (d, J=13.61), 138.09 (d, J=6.64 Hz), 157.23, 160.68 (d, J=248.56 Hz), 191.51; IR 1692 cm⁻; MS (ESI) m/z 331 (M+H)⁺, 372 (M+H+ACN)⁺.

Anal. for C₁₉H₂₃FO₂Si:

Calc'd: C: 69.06 H: 7.02

Found: C: 69.71 H: 7.34.

2-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde

0.32g (19%) of yellowish solid: mp 149-150° C.; ¹H NMR (Acetone-d₆):. δ 7.08-7.13 (2H, m), 7.62-7.67 (2H, m), 7.80-7.91 (2H, m), 7.94 (1H, dd, J=1.58 Hz), 8.93 (1H, s), 10.16 (1H, d, J=1.73 Hz); IR 1669 cm⁻; MS (ESI) m/z 215 (M−H)⁻¹.

Anal. for C₁₃H₉FO₂:

Calc'd: C: 72.22, H: 4.20

Found: C: 71.38, H: 4.12.

EXAMPLE 11 4′-{[tert-Butyl(dimethyl)silyl]oxy}-3-chloro[1,1, ′-biphenyl]-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-{[tert-butyl(dimethyl)silyl]oxy}-3-chloro-1,1′-biphenyl-4-carbaldehyde (405 mg, 1.17 mmol) with hydroxylamine hydrochloride (154 mg, 2.22 mmol) according to Method C to yield a yellowish oil which was used in the next step without purification: MS (ESI) m/z 362/364 (M+H)⁺.

EXAMPLE 12 4′-{[Tert-butyl(dimethyl)silyl]oxy}-2-fluoro-[1,1′-biphenyl]-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-{[tert-butyl(dimethyl)silyl]oxy}-2-fluoro-1,1′-biphenyl-4-carbaldehyde (450 mg, 1.36 mmol) with hydroxylamine hydrochloride (190 mg, 2.73 mmol) according to Method C to yield a white solid which was used in the next step without purification: MS (ESI) m/z 344 (M−H)⁻, 346 (M+H)⁺.

EXAMPLE 13 3-Fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting 4-bromo-2-fluoro-benzaldehyde (3g, 14.8 mmol) with 4-methoxyphenylboronic acid (2.70g, 17.8 mmol) according to Method B to yield 3.2g (94%) of white solid: mp 85-86° C.; ¹H NMR (DMSO-d₆): δ 3.83 (3H, s). 7.06-7.09 (2H, m), 7.70-7.75 (2H, m), 7.79-7.82 (2H, m), 7.88 (1H, t, J=7.96 Hz), 10.22 (1H, s); IR 1681 cm⁻¹; MS (ESI) m/z 231 (M+H)⁺.

Anal. for C₁₄H₁₁FO₂:

Calc'd: C: 73.03, H: 4.82

Found: C: 72.99, H: 4.73

EXAMPLE 14 3-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde

Method F. To a mixture of 3-fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde (0.986g, 4.29 mmol) in methylene chloride (35 mL) at 0° C. was slowly added boron tribromide (10.7 mL of 1 N solution in methylene chloride, 10.7 mmol). The mixture was allowed to warm slowly to room temperature and was stirred overnight. Water (4 mL) was injected into the mixture with stirring in an ice-water bath. The resulting mixture was poured into water and extracted with ethyl acetate (3×). The combined organic layers were washed with brine, dried over sodium sulfate, filtered, evaporation of the solvent and purification by silica column chromatography (15%-30% ethyl acetate-hexane) to yield 150 mg (16%) of the title compound as white solid. An analytical sample was afforded by reverse-phase preparative HPLC: mp 164-166° C.; ¹H NMR (Acetone-d₆): δ 76.98-7.01 (2H, m), 7.56 (1H, dd, J=12.49 Hz, J=1.64 Hz), 7.63-7.66 (1H, m), 7.67-7.70 (2H, m), 7.89 (1H, t, J=7.85 Hz), 8.88 (1H, (1H, s); MS (ESI) m/z 215 (M−H)⁻.

Anal. for C₁₃H₉FO₂:

Calc'd: C: 72.22, H: 4.20

Found: C: 71.83, H: 4.04

EXAMPLE 15 Trifluoro-methanesulfonic acid 2-chloro-4-formyl-phenyl ester

The title compound was prepared by reacting 3-chloro-4-hydroxybenzaldehyde (5g, 31.9 mmol) with trifluoromethanesulfonic anhydride (7.0 mL, 11.7g, 41.5 mmol) according to Method D to yield 9.15g (100%) of a yellow oil which was used directly in the next step without purification: ¹H NMR: δ 7.92 (1H, d, J=8.48 Hz), 8.07 (1H, dd, J=8.51 Hz, J=1.93 Hz), 8.30 (1H, d, J=1.92 Hz), 10.04 (1H, s).

EXAMPLE 16 2-Chloro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 2-chloro-4-formyl-phenyl ester (5g, 17.4 mmol) with 4-methoxyphenylboronic acid (3.44 g, 22.6 mmol) according to Method B to yield 3.83g (89%) of white solid: mp 85-87° C.; ¹H NMR (DMSO-d₆): δ 3.82 (3H, s), 7.07 (2H, d, J=8.83 Hz), 7.46 (2H, d, J=8.45 Hz), 7.63 (1H, d, J=7.87 Hz), 7.92 (1H, dd, J=7.87 Hz, J=1.56 Hz), 8.07 d, J=1.49 Hz); ¹³C NMR (DMSO-d₆): δ 55.14, 113.72, 127.80, 129.72, 130.42, 130.82, 132.15, 132.21, 136.11, 144.90, 159.33, 191.73; IR 1692 cm⁻¹; MS (EI) m/z 246/248 M⁺.

Anal. for C₁₄H₁₁ClO₂:

Calc'd: C: 68.16 H: 4.49

Found: C: 67.76 H: 4.36

EXAMPLE 17 2′-Chloro-4′-(dibromomethyl)-1,1′-biphenyl-4-ol

The title compound was prepared by reacting 2-chloro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde (800 mg, 3.25 mmol) with boron tribromide (8.1 mL of 1 N solution in methylene chloride, 8.13 mmol) according to Method F to yield 600 mg (50%) of yellowish solid: mp 107-108° C.; ¹H NMR (DMSO-d₆): δ 6.86 (2H, d, J=8.52 Hz), 7.29 (2H, d, J=8.50 Hz), 7.43 (1H, s), 7.45 (1H, d, J=8.12 Hz), 7.64 (1H, dd, J=8.07 Hz, J=1.83 Hz), 7.74 (1H, d, J=1.79 Hz), 9.71 (1H, bs); ¹³C NMR (DMSO-d₆): δ 40.66, 114.94, 125.66, 127.34, 128.14, 130.39, 130.87, 131.80, 140.95, 142.14, 157.36; MS (ESI) m/z 373/375/377/379 (M−H)⁻.

Anal. for C₁₃H₉Br₂ClO:

Calc'd: C: 41.48, H: 2.41

Found: C: 41.64, H: 2.14

EXAMPLE 18 Trifluoro-methanesulfonic acid 4-formyl-3-methoxy-phenyl ester

The title compound was prepared by reacting 4-hydroxy-2-methoxybenzaldehyde (3g, 19.7 mmol) with trifluoromethanesulfonic anhydride (4.3 mL, 7.2g, 25.6 mmol) according to Method D to yield a brown syrup which was used in the next step without purification: ¹H NMR: δ 3.97 (3H, s), 7.21 (1H, dd, J=8.64 Hz, J=2.17 Hz), 7.47 (1H, d, J=2.24 Hz), 7.87 (1H, d, J=8.64 Hz), 10.31 (1H, s).

EXAMPLE 19 Trifluoro-methanesulfonic acid 4-formyl-2-methyl-phenyl ester

The title compound was prepared by reacting 4-hydroxy-3-methylbenzaldehyde (2.5g, 18.4 mmol) with trifluoromethanesulfonic anhydride (4.0 mL, 6.75g, 23.9 mmol) according to Method D to yield a brown oil which was used directly in the next step without purification.

EXAMPLE 20 4′-Hydroxy-3-methoxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 4-formyl-3-methoxy-phenyl ester (11.0 mmol) with 4-tert-butyl-dimethylsilyoxyphenyl-boronic acid (3.50g, 13.86 mmol) according to Method B to yield 880 mg (35%, over two steps) of yellowish solid: mp 159-161° C.; ¹H NMR (DMDO-d₆): δ 4.01 (3H, s), 6.89 (2H, d, J=8.62 Hz), 7.31 (1H, d, J=8.16 Hz), 7.36 (1H, d, J=1.15 Hz), 7.66 (2H, d, J=8.63 Hz), 7.72 (1H, d, J=8.09 Hz), 9.80 (1H, s), 10.34 (1H, s); mp 159-161° C.; IR 1660 cm⁻; MS (ESI) m/z 227 (M−H)⁻, 229 (M+H)⁺.

Anal. for C₁₄H₁₂O₃:

Calc'd: C: 73.67, H: 5.30

Found: C: 73.44, H: 4.99.

EXAMPLE 21 4′-Hydroxy-2-methyl-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 4-formyl-2-methyl-phenyl ester (9.3 mmol) with 4-tert-butyl-dimethylsilyoxyphenylboronic acid (2.35g, 9.3 mmol) according to Method B to yield 1.12 mg (57%, over two steps) of yellowish solid: mp 94-96° C.; ¹H NMR (DMSO-d₆): ): δ 2.33 (3H, s), 6.86 (2H, d, J=8.55 Hz), 7.22 (2H, d, J=8.51 Hz), 7.39 (1H, d, J=7.81 Hz), 7.61 (1H, d, J=7.82 Hz), 7.81 (1H, s), 9.65 (1H, s), 10.00 (1H, s); IR 1670 cm⁻¹; MS (ESI) m/z 211 (M−H)⁻, 213 (M+H)⁺.

Anal. for C₁₄H₁₂O₂:

Calc'd: C: 79.23 H: 5.70

Found: C: 77.49 H: 5.67

EXAMPLE 22 3-Fluoro-4-methoxyphenylboronic acid

The title compound was prepared by reacting 4-bromo-2-fluoroanisole (10g, 0.049 moles) with n-butyl lithium (23.4 mL of 2.5 M solution in hexane, 0.059 moles) followed by triisopropyl borate (45.2 mL, 36.9g, 0.196 moles) according to Method A to yield 7.1g (85.2%) of a white solid: MS (ESI) m/z 169 (M−H)⁻.

EXAMPLE 23 3-Chloro-3′-fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 3-chloro-4-formyl-phenyl ester (2.8g, 9.62 mmol) with 3-fluoro-4-methoxyphenylboronic acid (1.8g, 10.6 mmol) according to Method B to yield 1.87g (74%, over two steps) of white solid: mp 116-118° C.; ¹H NMR (DMSO-d₆): δ 3.91 (3H, s), 7.30 (1H, t, J=8.79 Hz), 7.66-7.68 (1H, m), 7.79 (1H, dd, J=12.91 Hz, J=2.47 Hz), 7.85-7.87 (1H, m), 7.91 (1H, d, J=8.24 Hz), 7.96 (1H, d, J=1.65 Hz), 10.34 (1H, s); IR 1688 cm⁻¹; MS (ESI) m/z 265/267 (M+H)⁺.

Anal. for C₁₄H₁₀ClFO₂:

Calc'd: C: 63.53, H: 3.81

Found: C: 63.29, H: 3.63.

EXAMPLE 24 3-Chloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting 3-chloro-3′-fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde (990 mg, 3.75 mmol) with boron tribromide (11.25 mL of 1 N solution in methylene chloride, 11.25 mmol) according to Method F to yield 940 mg (100%) of yellowish solid. The compound was used in the next step without purification. The analytical sample was obtained by HPLC purification: mp 206-208° C.; ¹H NMR (DMSO-d₆): δ 7.06 (1H, t, J=8.79 Hz), 7.51-7.53 (1H, m), 7.71 (1H, d, J=2.47 Hz, J=12.63 Hz), 7.81-7.83 (1H, m), 7.89 (1H, d, J=7.96 Hz), 7.91 (1H, d, J=1.66 Hz), 10.329(1H, s), 10.330 (1H, s); IR 1667 cm⁻¹; MS (ESI) m/z 249/251 (M−H)⁻.

Anal. for C₁₃H₈CIFO₂:

Calc'd: C: 62.29, H: 3.22

Found: C: 61.97, H: 3.21.

EXAMPLE 25 3-Chloro-3′,5′-difluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde

The title compound was prepared by reacting trifluoro-methanesulfonic acid 3-chloro-4-formyl-phenyl ester (1g, 3.5 mmol) with 3,5-difluoro-4-tert-butyldimethylsilyoxy-boronic acid (1.1g, 3.8 mmol) according to Method B to yield 0.56g (60%) of yellow solid: mp 233-235° C.; ¹H NMR (DMSO-d,): δ 7.64 (2H, d, J=7.85 Hz), 7.85-7.91 (2H, m), 7.98 (1H, s), 10.33 (1H, s), 10.70 (1H, bs); IR 1665 cm⁻¹; MS (ESI) m/z (267/269) (M−H)⁻.

Anal. for C₁₃H₇CIF₂O₂:

Calc'd: C: 58.12, H: 2.63

Found: C: 57.79, H: 2.72.

EXAMPLES 26 and 27

Trifluoro-methanesulfonic acid 3-chloro-4-formyl-phenyl ester (3.78g, 13.12 mmol) was reacted with with 4-methoxy-2-methylphenylboronic acid (2.61g, 15.7 mmol) according to Method B to produce two compounds:

3-Chloro-4′-methoxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde

2.18g (64%) white solid :mp 77-79° C.; ¹H NMR (DMSO-d₆): δ 2.26 (3H, s), 3.79 (3H, s), 6.88 (1H, dd, J=8.41 Hz, J=2.66 Hz), 6.93 (1H, d, J=2.50 Hz), 7.23 (1H, J=8.40 Hz), 7.50 (1H, dd, J=7.93 Hz, J=1.32 Hz), 7.58 (1H, d, J=1.53 Hz), 7.91 (1H, d, J=7.57 Hz), 10.36 (1H, s); IR 1682 cm⁻¹; MS (ESI) m/z 261/263 (M+H) ⁺.

Anal. for C₁₅H₁₃ClO₂:

Calc'd: C: 69.10, H: 5.03

Found: C: 69.13, H: 4.73.

4,4″-Dimethoxy-2,2″-dimethyl-1,1′:3′,1″-terphenyl-4′-carbaldehyde

0.56g (12%) colorless; ¹H NMR (DMSO-d₆): δ 2.10 (3H, s), 2.29 (3H, s), 3.78 (3H, s), 3.80 (3H, s), 6.85-6.88 (2H, m), 6.91 (1H, d, J=2.38 Hz), 6.95 (1H, d, J=2.38 Hz), 7.18 (1H, d, J=8.32 Hz), 7.24-7.25 (2H, m), 7.52 (1H, dd, J=7.74 Hz, J=1.78 Hz), 7.95 (1H, d, J=8.33 Hz), 9.68 (1H, s); IR 1679 cm⁻; MS (ESI) m/z 347 (M+H)⁺.

Anal. for C₂₃H₂₂O₃:

Calc'd: C: 79.74, H: 6.40

Found: C: 79.25, H: 6.05.

EXAMPLE 28 3-Chloro-4′-hydroxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde

3-Chloro-4′-methoxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde (1.0g, 3.84 mmol) and pyridinium HCl (6g) in a sealed tube was heated at 195° C. with stirring for 1 hr. The reaction mixture was cooled to room temperature and stirred with 2 N HCl solution and ethyl acetate. The organic layer was separated and the aqueous layer was extracted with ethyl acetate (×2). The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and evaporation of the solvent provided (1g) dark green solid. The product was used without any further purification. An analytical sample was obtained by HPLC purification giving a white solid; mp 125-127° C.; ¹H NMR (DMSO-d₆): δ 2.21 (3H, s), 6.68-6.72 (2H, m), 7.11 (1H, d, J=8.15 Hz), 7.47 (1H, d, J=7.89 Hz), 7.55 (1H, d, J=1.48 Hz), 7.89 (1H, d, J=7.98 Hz), 9.62 (1H, s), 10.2=35 (1H, s); MS (ESI) m/z 245/247 (M−H)⁻, 247/249 (M+H)⁺.

Anal. for C₁₄H₁₁ClO₂:

Calc'd: C: 68.16, H: 4.49

Found: C: 67.63, H: 4.43.

EXAMPLE 29 4′-Hydroxy-3-methyl[1,1′-biphenyl]-4-carbaldehyde oxime

A mixture of 4′-hydroxy-3-methyl[1,1′-biphenyl]-4-carbaldehyde (310 mg, 1.46 mmol), hydroxylamine hydrochloride (203 mg, 2.92 mmol) and pyridine (236 ul, 2.92 mmol) in 15 mL absolute methanol was refluxed for 2.5 h. The solvent was removed under reduced pressure and the mixture was dissolved in ethyl acetate and water, extracted with ethyl acetate (×3), washed with brine, dried over sodium sulfate, and filtered. Evaporation of the solvent and purification by recrystallization (ethyl acetate, acetone and hexane) gave 177 mg (53%) of the title compound as a yellowish solid: mp 195-197° C.;

¹H NMR (DMSO-d₆): δ 2.43 (3H, s), 6.84 (2H, d, J=8.48 Hz), 7.42-7.45 (2H, m), 7.5 (2H, d, J=8.51 Hz), 7.66 (1H, d, J=8.00 Hz), 8.32 (1H, s), 9.60 (1H, s), 11.25 (1H, s); ¹³C NMR (DMSO-d₆): δ 19.62, 115.60, 123.40, 126.60, 127.56, 127.99, 129.05, 130.03, 136.34, 140.43, 146.80, 157.24; MS (ESI) n/z 226 (M−H)⁻, 228 (M+H)⁺.

Anal. for C₁₄H₁₃NO₂:

Calc'd: C: 73.99, H: 5.77, N: 6.16

Found: C: 73.81, H: 5.75, N: 6.04.

EXAMPLE 30 4′-Hydroxy[1,1′-biphenyl]-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-hydroxy[1,1′-biphenyl]-4-carbaldehyde (1.03 mmol) with hydroxylamine hydrochloride (140 mg, 2 mmol) according to Method C to yield 193 mg (79%, over two steps) of yellowish solid: mp 207-210° C.; ¹H NMR (DMSO-d₆): δ 6.85 (2H, d, J=8.37 Hz), 7.53 (2H, d, J=8.39 Hz), 7.62 (4H, s), 8.15 (1H, s), 9.62 (1H, s), 11.21 (1H, s); MS (ESI) m/z 212 (M−H)⁻.

Anal. for C₁₃H₁₁NO₂:

Calc'd: C: 73.23, H: 5.20, N: 6.57

Found: C: 72.78, H: 5.41, N: 6.38.

EXAMPLE 31 3-Chloro-4′-hydroxy[1,1′-biphenyl]-4-carbaldehyde oxime

Method E. Tetrabutylammonium fluoride (1.29 mL of 1.0 M solution in tetrahydrofuran, 1.29 mmol) was added into a solution of 4′-{[tert-butyl(dimethyl)silyl]oxy}-3-chloro[1,1′-biphenyl]-4-carbaldehyde oxime (1.17 mmol) in 10 mL tetrahydrofuran. The mixture was stirred at room temperature for 10 min then poured into ethyl acetate and water. The resulting layers were separated and the aqueous layer was extracted with ethyl acetate (3×). The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and and the solvent removed under vacuum. Purified by silica chromatography (20%-30% ethyl acetate-hexane) provided 0.186 mg (64%) of the title compound as yellowish solid: mp 187-189° C.; ¹H NMR (DMSO-d₆): δ 6.86(2H, d, J=8.55 Hz), 7.56-7.63 (3H, m), 7.71 (1H, d, J=1.60 7.84 (1H, d, J=8.26 Hz), 8.36 (1H, s), 9.75 (1H, s), 11.66 (1H, s); MS (ESI) m/z (M−H)⁻, 248 (M+H)⁺.

Anal. for C₁₃H₁₀ClNO₂:

Calc'd: C: 63.04, H: 4.07, N: 5.66

Found: C: 62.96, H: 4.10, N: 5.42.

EXAMPLE 32 2-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-{[tert-butyl(dimethyl)silyl]oxy}-2-fluoro-[1,1′-biphenyl]-4-carbaldehyde oxime (1.02 mmol) with tetrabutylammonium fluoride (1.12 mL of 1.0 M solution in tetrahydrofuran, 1.12 mmol) according to Method E to yield 198 mg (84%) of a white solid: mp 178-180° C.; ¹H NMR (DMSO-d₆): δ 6.84-6.89 (2H, m), 7.39-5.54 (5H, m), 8.17 (1H, s), 9.71 (1H, s), 11.43 (1H, s); MS (ESI) m/z 230 (M−H)⁻, 232 (M+H)⁺.

Anal. for C₁₃H₁₀FNO₂:

Calc'd: C: 67.53, H: 4.36, N: 6.06

Found: C: 67.13, H: 4.11, N: 6.00.

EXAMPLE 33 3-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (154 mg, 0.713 mmol) with hydroxylamine hydrochloride (99 mg, 1.43 mmol) according to Method C to yield 156 mg (95%) of yellowish solid: mp 181-183° C.; ¹H NMR (DMSO-d₆): δ 6.84-6.87 (2H, m), 7.48-7.53 (2H, m), 7.57-7.60 (2H, m), 7.76 (1H, t, J=8.14 Hz), 8.22 (1H, s), 9.74 (1H, s), 11.56 (1H, s); MS (ESI) m/z 230 (M−H)⁻, 232 (M+H)⁺.

Anal. for C₁₃H₁₀FNO₂:

Calc'd: C: 67.53, H: 4.36, N: 6.06

Found: C: 68.10, H: 4.28, N: 6.01.

EXAMPLE 34 2-Chloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 2′-chloro-4′-(dibromomethyl)-1,1′-biphenyl-4-ol (270 mg, 0.722 mmol) with hydroxylamine hydrochloride (185 mg, 2.66 mmol) according to Method C to yield 160 mg (90%) of white solid: mp 178-179° C.; ¹H NMR (DMSO-d₆): δ 6.85 (2H, d, J=8.54 Hz), 7.28 (2H, d, J=8.51 Hz), 7.39 (1H, d, J=7.98 Hz), 7.60 (1H, dd, J=7.65 Hz, J=1.42 Hz), 7.72 (1H, d, J=1.34 Hz), 8.18 (1H, s), 9.67 (1H, s), 11.45 (1H, s); MS (ESI) m/z 246/248 (M−H)⁻.

Anal. for C₁₃H₁₀ClNO₂:

Calc'd: C: 63.04, H: 4.07, N: 5.66

Found: C: 63.07, H: 3.99, N: 5.67.

EXAMPLE 35 4′-Hydroxy-3-methoxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-hydroxy-3-methoxy-1,1′-biphenyl-4-carbaldehyde (225 mg, 0.986 mmol) with hydroxylamine hydrochloride (137 mg, 1.97 mmol) according to Method C to yield 210 mg (88%) of yellowish solid: mp 228-230° C.; ¹H NMR (DMSO-d₆): δ 3.91 (3H, s), 6.85 (2H, d, J=8.29 Hz), 7.18 (1H, d, J=8.08 Hz), 7.21 (1H, s), 7.56 (2H, d, J=8.59 Hz), 7.68 (1H, d, J=7.98 Hz), 8.28 (1H, s), 9.63 (1H, s), 11.19 (1H, s); MS (ESI) m/z 242 (M−H)⁻, 244 (M+H)⁺.

Anal. for C₁₄H₁₃NO₃:

Calc'd: C: 69.12, H: 5.39, N: 5.76

Found: C: 68.87, H: 5.29, N: 5.64.

EXAMPLE 36 4′-Hydroxy-2-methyl-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 4′-hydroxy-2-methyl-1,1′-biphenyl-4-carbaldehyde (350 mg, 1.65 mmol) with hydroxylamine hydrochloride (230 mg, 3.30 mmol) according to Method C to yield 360 mg (96%) of white solid: mp 169-171° C.; ¹H NMR (DMSO-d₆): δ 2.25 (3H, s), 6.82 (2H, d, J=8.52 Hz), 7.16 (2H, d, J=8.45 Hz), 7.18 (1H, d, J=7.84 Hz), 7.44 (1H, d, J=7.93 Hz), 7.47 (1H, s), 8.11 (1H, s), 9.52 (1H, s), 11.19 (1H, s); MS (ESI) m/z 226 (M−H)⁻, 228 (M+H)⁺.

Anal. for C₁₄H₁₃NO₂:

Calc'd: C: 73.99, H: 5.77, N: 6.16

Found: C: 73.72, H: 5.63, N: 6.37.

EXAMPLE 37 3-Chloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3-chloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (1.52 mmol) with hydroxylamine hydrochloride (233 mg, 3.34 mmol) according to Method C to yield 260 mg (66%) of yellowish solid: mp 198-200° C.; ¹H NMR (DMSO-d₆): δ 7.03 (1H, t, J=8.79 Hz), 7.41-7.43 (1H, m), 7.60 (1H, dd, J=12.91 Hz, J=2.20 Hz), 7.64-7.66 (1H, m), 7.77 (1H, d, J=1.92 Hz), 7.84 (1H, d, J=8.24 Hz), 8.36 (1H, s),10.16 (1H, bs), 11.68 (1H, bs); MS (ESI) m/z 264/266 (M−H)⁻, 266/268 (M+H)⁺.

Anal. for C₁₃H₉ClFNO₂:

Calc'd: C: 58.77, H: 3.41, N: 5.27

Found: C: 58.67, H: 3.65, N: 4.99.

EXAMPLE 38 3-Chloro-3′, 5′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3-chloro-3′,5′-difluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (200 mg, 0.746 mmol) with hydroxylamine hydrochloride (156 mg, 2.24 mmol) according to Method C to yield 100 mg (47%) of white solid: mp 216-219° C.; ¹H NMR (DMSO-d₆): δ 7.54 (2H, d, J=8.51 Hz), 7.70 (1H, d, J=7.97 Hz), 7.84-7.86 (2H, m), 8.37 (1H, s), 10.52 (1H, s), 11.74 (1H,s); MS (ESI) m/z 282/284 (M−H)⁻, 284/286 (M+H)⁺.

Anal. for C₁₃H₈CIF₂NO₂:

Calc'd: C: 55.05, H: 2.84, N: 4.94

Found: C: 54.96, H: 3.02, N: 4.75.

EXAMPLE 39 3-Chloro-4′-hydroxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3-chloro-4′-hydroxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde (500 mg, 2.03 mmol) with hydroxylamine hydrochloride (425 mg, 6.10 mmol) in anhydrous tetrahydrofuran (50 mL) and methanol (20 mL) according to Method C to yield 350 mg (57% over two steps) of white solid: mp 169-171° C.; ¹H NMR (DMSO-d₆): δ 2.19 (3H, s), 6.65-6.70 (2H, m), 7.06 (1H, d, J=8.14 Hz), 7.31 (1H, d, J=8.05 Hz), 7.41 (1H, d, J=1.40 Hz), 7.83 (1H, d, J=8.08 Hz), 8.38 (1H, s), 9.51 (1H, s), 11.69 (1H, s); MS (ESI) m/z 260/262 (M−H)⁻, 262/264 (M+H)⁺.

Anal. calc'd for C₁₄H₁₂ClNO₂:

Calc'd: C: 64.25; H: 4.62; N: 5.35

Found: C: 63.87; H: 4.43; N: 5.31

EXAMPLE 40 (2,6-Dichloro-4-methoxy-phenyl)-methanol

A mixture of 3,5 dichloroanisole (16.;39g, 92.59 mmol), HCl (250 mL of concentrated solution), and sulfuric acid (2.5 mL of concentrated solution) was stirred at 60° C. overnight. The mixture was cooled to room temperature and the organic layer was removed. The aqueous layer was extracted with dichloromethane (2×100 mL). The combined organic layers were washed with water and the solvent was removed by evaporation. To the remaining oil was added NaOH (180 mL of 1N solution) and dioxane (85 mL). The mixture was stirred at reflux for 3 hours and cooled to room temperature. The organic layer was removed and the aqueous layer was extracted with dichloromethane (3×100 mL). The combined organic layers were washed with water, washed with brine, dried over sodium sulfate, and filtered. The residue was purified on silica (90% hexanes-10% ethyl acetate) to yield 5.82g (30%) of the title compound as a white solid: mp 71-72° C.; ¹H NMR (CDCl₃): δ 1.88 (1H, s), 3.73 (3H, s), 4.81 (2H, s), 6.81 (2H, s); MS (EI) m/z 206/208/210 (M⁺⁻).

Anal. for C₈H₈Cl₂O₂:

Calc'd: C: 46.41 H:3.89

Found: C:46.38 H:3.69.

EXAMPLE 41 2,6-Dichloro-4-methoxy-benzaldehyde

A suspension of (2,6-dichloro-4-methoxy-phenyl)-methanol (5.69g, 27.49 mmol) and MnO₂ (15g) in benzene (100 mL) was stirred at reflux, utilizing a Dean-Stark trap, overnight. The suspension was cooled to room temperature, filtered through Celite, and the solvent was removed by evaporation to yield 4.69g (83%) of crude white solid. An analytical sample was obtained by recrystallization from methanol to yield white needle crystals: mp 104-106° C.; ¹H NMR (DMSO-d₆): δ 3.90 (3H, s), 7.21 (2H, s), 10.29 (1H, s); MS (EI) m/z 204/206/218 (M⁺⁻).

Anal. for C₈H₆Cl₂O₂:

Calc'd: C:46.86 H:2.

Found: C:46.67 H:2.89.

EXAMPLE 42 2,6-Dichloro-4-hydroxy-benzaldehyde

To a solution of 2,6-dichloro-4-methoxy-benzaldehyde (3.44g, 16.8 mmol) in dichloromethane (120 mL) at 0° C. was slowly added boron tribromide (42 mL of 1N in dichloromethane, 42 mmol). The solution was allowed to warm to room temperature while stirring overnight and was quenched with saturated sodium bicarbonate solution (250 mL). The resulting mixture was extracted with ethyl acetate (3×200 mL). The combined organic layers were washed with water, washed with brine, dried over sodium sulfate, and filtered. The solvent was removed by evaporation and the residue was purified on silica (70% hexanes-30% ethyl acetate) to yield 2.19g (68%) of a pink solid. Trituration with ethyl acetate-hexanes yielded an analytical sample of the title compound as a white solid: mp: 214-217° C.; ¹H NMR (DMSO-d₆): δ 6.95 (2H, s), 10.26 (1H, s), 11.44 (1H, s); MS (EI) m/z 189.8/191.8/193.8 (M⁺⁻).

Anal. for C₇H₄Cl₂O₂:

Calc'd: C:44.02 H:2.11

Found: C:44.08 H:2.07.

EXAMPLE 43 3,5-Dichloro-4-formyl-phenyl trifluoromethanesulfonate

The title compound was prepared by reacting 2,6-dichloro-4-hydroxy-benzaldehyde (2.35g, 12.3 mmol) with trifluoromethanesulfonic anhydride (4.51g, 16.0 mmol) according to method E to yield a 3.45g (87%) of a clear yellow oil. TLC analysis of this oil indicated that it appeared to decompose into the starting phenol upon standing. ¹H NMR (DMSO-d₆): δ 8.03 (2H, s), 10.31 (1H, s).

EXAMPLE 44 3,5-Dichloro-4′hydroxy-biphenyl-4-carbaldehyde

The title compound was prepared by reacting 3,5-dichloro-4-formyl-phenyl trifluoromethanesulfonate (0.73g, 2.26 mmol) with 4-tert-butyldimethylsilyloxyphenyl boronic acid (0.80g, 3.2 mmol) according to method C to yield 0.30g (50%) of a yellow solid: mp:178-180° C.; ¹H NMR (DMSO-d₆): δ 6.88 (2H, d, J=8.84 Hz), 7.72 (2H, d, J=8.71 Hz), 7.84 (2H, s), 9.95 (1H, s), 10.38 (1H, s); MS (EI) m/z 266.0/268.0/270.0 (M⁺).

Anal. for C₁₃H₈Cl₂O₂.0.5 H₂O:

Calc'd: C:56.55 H:3.29

Found: C:56.36 H:2.90.

EXAMPLE 45 2,3-Dichloro-4-methoxybenzaldehyde

To a solution of 2,3-dichloroanisole (10.00g, 56.6 mmol) in anhydrous dichloromethane (45 ml) was added TiCl₄ (10.5 ml, 96.1 mmol) quickly. α, α′-dichloromethyl methyl ether (5.1 ml, 56.6 mmol) was then added slowly and the inner temperature was maintained between 15° C. to 20° C. The mixture was stirred room temperature for 5 h, poured into crushed ice slowly, extracted with dichloromethane (3×), washed with saturated sodium bicarbonate until pH=7, then washed with brine. The organic layer was dried over anhydrous sodium sulfate, concentrated to give 11.34g (98%) of white solid. An analytical sample was afforded by reverse-phase preparative HPLC: mp 112-113° C.; ¹H NMR (CDCl₃): δ 4.01 (3H, s), 6.97 (1H, d, J=8.77 Hz), 7.90 (1H, d, J=8.82 Hz), 10.36 (1H, s); MS (ESI) m/z 205/207/209 (M+H)⁺.

Anal. for C₈H₆Cl₂O₂:

Calc'd: C:46.86 H:2.95;

Found: C:46.92 H:2.70.

EXAMPLE 46 2,3-Dichloro-4-hydroxybenzaldehyde

The title compound was prepared by reacting 2,3-dichloro-4-methoxybenzaldehyde (10g, 49 mmol) with boron tribromide (147 ml of 1N solution in CH₂Cl₂, 147 mmol) according to method D to yield 11.3g dark grey solid which is mainly the designed product indicated by ¹H-NMR. It was triturated with 30% CHCl₃ in hexane to give 3.6g of grey solid as pure product. An analytical sample was afforded as white solid by reverse-phase preparative HPLC: mp 176-178° C.; ¹H NMR (DMSO-d₆): δ 7.10 (1H, d, J=8.68 Hz), 7.74 (1H, d, J=8.67 Hz), 10.16 (1H, s), 11.95 (1H, s); MS (ESI) m/z 189/191/193 (M−H)⁻, 193/191/195 (M+H)⁺.

Anal. for C₇H₄Cl₂O₂

Calc'd: C: 44.02 H: 2.11

Found: C: 43.87 H: 1.67.

EXAMPLE 47 Trifluoro-methanesulfonic acid 2,3-dichloro-4-formyl-phenyl ester

The title compound was prepared by reacting 2,3-dichloro-4-hydroxybenzaldehyde (2.50g, 13.2 mmol) with trifluoromethanesulfonic anhydride (2.88 ml, 4.80g, 17.1 mmol) according to example 43 to yield 3.69g (82%) of a brown crystal which was used directly in the next step without purification. An analytical sample was afforded as white solid by silica chromatography (5% ethyl acetate-hexane): mp 44-45° C.; ¹H NMR (DMSO-d₆): δ 7.88 (1H, d, J=8.74 Hz), 8.02 (1H, d, J=8.81 Hz), 10.28 (1H, s); MS (EI) m/z 322/324/326 (M)⁺.

Anal. for C₈H₃Cl₂F₃O₄S:

Calc'd: C: 29.74 H:0.94;

Found: C: 30.19H:0.86.

EXAMPLES 48-50

Trifluoro-methanesulfonic acid 2,3-dichloro-4-formyl-phenyl ester (1.39g, 4.33 mmol) was reacted with boronic acid 21 (1.20g, 4.76 mmol) according to method B to produce the following three compounds:

2,3-Dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (48).

310 mg (27%) of white solid: mp 172-174° C.; ¹H NMR (DMSO-d₆): δ 6.86-6.91 (2H, m), 7.32-7.35 (2H, m), 7.53 (1H, dd, J=7.94 Hz, J=0.45 Hz), 7.85 (1H, d, J=8.01 Hz), 9.85 (1H, s), 10.35 (1H, s); MS (ESI) m/z 265/267/269 (M−H)⁻.

Anal. for C₁₃H₈C₂O₂:

Calc'd: C:58.46 H:3.02;

Found: C:57.75 H:2.82.

2-Chloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (49)

90 mg (9%) of off white solid: mp 114-116° C.; ¹H NMR (DMSO-d₆): δ 6.85-6.90 (2H, m), 7.32-7.36 (2H, m), 7.61(1H, d, J=7.87 Hz), 7.89 (1H, dd, J=1.55 Hz), 8.05 (1H, d, J=1.52 Hz), 9.79 (1H, s), 10.02 (1H, s); MS (ESI) m/z 231/233 (M−H)⁻, 233/235 (M+H)⁺.

Anal. for C₁₃H₉Cl₂O₂:

Calc'd: C:67.11 H:3.90

Found: C:67.44 H:3.87

2′-Dichloro-4,4″-dihydroxy-1,1′:3′,1″-terphenyl-4′-carbaldehyde (50)

130 mg (9%) of off white solid: mp 222-223° C.; ¹H NMR (DMSO-d₆): δ 6.85-6.88 (2H, m), 6.88-6.91 (2H, m), 7.17-7.20 (2H, m), 7.31-7.35 (2H, m), 7.52 (1H, dd, J=7.96 Hz, J=0.89 Hz), 7.84 (1H, d, J=8.07 Hz), 9.55 (1H, d, J=0.77 Hz), 9.73 (1H, s), 9.74 (1H, s); MS (ESI) m/z 323/325 (M−H)⁻, 325/327 (M+H)⁺.

Anal. for C₁₉H₁₃ClO₃:

Calc'd: C:70.27 H:4.03

Found: C:69.80 H:3.88

EXAMPLE 51 2,3-Dichloro-3′-fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting trifluoro-methanesulfonic acid 2,3-dichloro-4-formyl-phenyl ester (1.90g, 5.90 mmol) with 21 (1.30g, 7.67 mmol) according to method B to yield 0.84g (47%) of white solid: mp 160-164° C.; ¹H NMR (DMDO-d₆): δ 3.90 (3H, m), 7.28-7.30 (2H, m), 7.41-7.43 (1H, m), 7.57 (1H, d, J=8.30 Hz), 7.87 (1H, d, J=7.81 Hz), 10.35 (1H, s); MS (EI) m/z 298/300/302 (M)⁺.

Anal. for C₁₄H₉Cl₂O₂:

Calc'd: C:56.21 H:3.03

Found: C:57.55 H:2.97.

EXAMPLES 52 and 53

2,3-Dichloro-3′-fluoro-4′-methoxy-1,1′-biphenyl-4-carbaldehyde (0.72g, 2.42 mmol) was reacted with boron tribromide (7.25 ml of 1N solution in CH₂Cl₂, 7.25 mmol) according to method E to produce the following two compounds:

2′,3′-Dichloro-4′-(dibromomethyl)-3-fluoro-1,1′-biphenyl-4-ol (52)

130 mg (13%) of grey thick syrup: ¹H NMR (DMSO-d₆): δ 7.04 (1H, t, J=8.54 Hz), 7.11 (1H, dd, J=8.41 Hz, J=1.97 Hz), 7.32 (1H, dd, J=12.18 Hz , J=1.94 Hz), 7.51 (1H, d, J=8.27 Hz), 7.54 (1H, s), 7.95 (1H, d, J=8.23 Hz), 10.23 (1H, s); MS (ESI) m/z 425/427/429 (M−H)⁻.

Anal. for C₁₃H₇Br₂Cl₂FO₂:

Calc'd: C:36.40 H: 1.65

Found: C:37.60 H: 1.69.

2,3-Dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (53)

140 mg (20%) of white solid: mp 170-171° C.; ¹H NMR (DMSO-d₆): δ 7.07 (1H, t, J=8.60 Hz), 7.15 (1H, dd, J=8.40 Hz, J=1.79 Hz), 7.35 (1H, dd, J=12.15 Hz, J=1.87 Hz), 7.56 (1H, d, J=7.97 Hz), 7.86 (1H, d, J=8.09 Hz ), 10.31 (1H, s), 10.35 (1H, s); MS (ESI) m/z 283/285/287 (M−H)⁻.

Anal. for C₁₃H₇Cl₂FO₂:

Calc'd:C:54.77 H:2.47

Found: C:54.93 H:2.18.

EXAMPLE 54 3,5-Dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3,5-dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (170 mg, 0.637 mmol) with hydroxylamine hydrochloride (89 mg, 1.27 mmol) according to Method F to yield 160 mg (89%) of a white solid: mp 183-186° C.; ¹H NMR (DMSO-d₆): δ 6.86 (2H, d, J=8.79 Hz), 7.63 (2H, d, J=8.79 Hz), 7.76 (2H, s), 8.25 (1H, s), 9.81 (1H, s), 11.78 (1H, s); MS (ESI) m/z 280/282/284 (M−H)⁻, 282/284/286 (M+H)⁺.

EXAMPLE 55 3,5-Dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 3,5-dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde (290 mg, mmol) with hydroxylamine hydrochloride (140 mg, 1.27 mmol) according to Method F to yield 260 mg (85%) of a white solid: mp 185-190° C.; ¹H NMR (DMSO-d₆): δ 7.03 (1H, t, J=8.86 Hz), 7.46-7.49 (1H, m), 7.68 (1H, dd, J=12.74 Hz, J=2.26 Hz), 7.82 (2H, s), 8.25 (1H, s), 10.24 (1H, s), 11.80 (1H, s); MS (ESI) m/z 298/300/302 (M−H)⁻, 300/302/304 (M+H)⁺.

Anal. for C₁₃H₈Cl₂FNO₂.0.2 H₂O:

Calc'd: C:51.41 H:2.79 N:4.61

Found: C:51.70 H:2.75 N:4.21.

EXAMPLE 56 2,3-Dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime

The title compound was prepared by reacting 48 (140 mg, 0.526 mmol) with hydroxylamine hydrochloride (110 mg, 1.58 mmol) according to method F to yield 148 mg (100%) of off white solid: mp 208-210° C.; ¹H NMR (DMSO-d₆): δ 6.84-6.87 (2H, m), 7.26-7.29 (2H, m), 7.36 (1H, d, J=7.94 Hz). 7.80 (1H, d, J=8.20 Hz), 8.41 (1H, s), 9.72 (1H, s), 11.83 (1H, s); MS (ESI) m/z 280/282/284 (M−H)⁻, 282/284/286 (M+H)⁺.

Anal. for C₁₃H₉Cl₂NO₂:

Calc'd: C:55.35 H:3.22 N:4.96

Found: C:55.78 H:3.59 N:4.44.

EXAMPLE 57

52 (85 mg, 0.20 mmol) was reacted with hydroxylamine hydrochloride (376 mg, 5.39 mmol) and pyridine (0.43 ml, 5.34 mmol) for 8 days according to method C to produce the following two compounds:

2,3-Dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime (57)

17.6 mg (30%) of white solid: mp 225-227° C.; ¹H NMR (DMSO-d₆): δ 7.04 (1H, t, J=8.54 Hz ), 7.10 (1H, dd, J=8.35 Hz , J=1.88 Hz ), 7.28 (1H, dd, J=Hz , J=2.01 Hz), 7.39 (1H, d, J=8.14 Hz), 7.81 (1H, d, J=8.15 Hz), 8.41 (1H, s), 10.18 (1H, s), 11.87 (1H, s); MS (ESI) m/z 298/300/302 (M−H)⁻, 300/302/304 (M+H)⁺.

Anal. for C₁₃H₈Cl₂FNO₂.0.09 TFA:

Calc'd: C:51.00 H:2.63 N:4.51

Found: C:50.97 H:2.37 N:4.33.

Methyl 2,3-dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carboxylate

16.9 mg (27%) of white solid: mp 152-154° C.; ¹H NMR (DMSO-d₆): δ 3.90 (3H, s), 7.05 (1H, t, J=8.54 Hz), 7.11 (1H, dd, J=8.41 H, J=1.55 Hz), 7.31 (1H, dd, J=12.16 Hz, J=1.68 Hz), 7.47 (1H, d, J=8.02 Hz), 7.76 (1H, d, J=8.64 Hz); MS (ESI) m/z 313/315/317 (M+H)⁺.

Anal. for C₁₄H₉Cl₂FO₃:

Calc'd: C:53.36 H:2.88

Found: C:51.94 H:2.54.

EXAMPLE 58 Table 1. 4′-Hydroxy-Biphenyl-carbaldehyde Oxime Derivatives

Ex. R¹ R² R³ R⁵ R⁶ R⁷ ER_(β)(nM) ER_(α)(nM) 29 H Me H H H H 163 3193 30 H H H H H H 3840 >5000 31 H Cl H H H H 85 1540 32 H H F H H H 421 3450 33 H F H H H H 161 1720 34 H H Cl H H H 98 398 35 H OMe H H H H 1058 7990 36 H H Me H H H 585 2821 37 H Cl H H F H 54 1910 38 H Cl H H F F 268 >7000 39 H Cl H Me H H 27 174 54 Cl Cl H H H H 8 64 55 Cl Cl H H F H 9 270 56 H Cl Cl H H H 49 851 57 H Cl Cl H F H 81 1957

The results obtained in the standard pharmacologic test procedure demonstrate that the compounds of this invention are estrogenic compounds, some with strong preferential affinity for the ERβ receptor. The compounds of this invention range from having high preferential affinity for ERβ over ERα to almost equal affinity for both receptors. Thus, compounds of this invention will span a range of activity based, at least partially, on their receptor affinity selectivity profiles. Additionally, because each novel receptor ligand complex is unique and thus its interaction with various coregulatory proteins is unique, compounds of this invention will display different modulatory behavior depending on the cellular context they are in. For example, in some cell-types, it is possible for a compound to behave as an estrogen agonist while in other tissues, an antagonist. Compounds with such activity have sometimes been referred to as SERMs (Selective Estrogen Receptor Modulators). Unlike many estrogens, however, many of the SERMs do not cause increases in uterine wet weight. These compounds are antiestrogenic in the uterus and can completely antagonize the trophic effects of estrogen agonists in uterine tissue. These compounds, however, act as estrogen agonists in the bone, cardiovascular, and central nervous systems. Due to this tissue selective nature of these compounds, they are useful in treating or preventing in a mammal disease states or syndromes which are caused or associated with an estrogen deficiency (in certain tissues such as bone or cardiovascular) or an excess of estrogen (in the uterus or mammary glands).

Even beyond such cell-specific modulation, compounds of this invention also have the potential to behave as agonists on one receptor type while behaving as antagonists on the other. For example, it has been demonstrated that compounds can be an antagonist on ERβ while being an agonist on ERα (Meyers, Marvin J.; Sun, Jun; Carlson, Kathryn E.; Katzenellenbogen, Benita S.; Katzenellenbogen, John A. J. Med. Chem. (1999), 42(13), 2456-2468). Such ERSAA (Estrogen Receptor Selective Agonist Antagonist) activity provides for pharmacologically distinct estrogenic activity within this series of compounds.

Standard pharmacological test procedures are readily available to determine the activity profile of a given test compound. The following examples briefly summarize several representative test procedures. Standard pharmacological test procedures for SERMs are also provided in U.S. Pat. Nos. 4,418,068 and 5,998,402.

EXAMPLE 59 Rat Uterotrophic/Antiuterotrophic Test Procedure

The estrogenic and antiestrogenic properties of the compounds can be determined in an immature rat uterotrophic assay (4 day) that (as described previously by L. J. Black and R. L. Goode, Life Sciences, 26, 1453 (1980). Immature Sprague-Dawley rats (female, 18 days old) were tested in groups of six. The animals are treated by daily ip injection with 10 uG compound, 100 uG compound, (100 uG compound+1 uG 17β-estradiol) to check antiestrogenicity, and 1 uG 17β-estradiol, with 50% DMSO/50% saline as the injection vehicle. On day 4 the animals are sacrificed by CO₂ asphyxiation and their uteri removed and stripped of excess lipid, any fluid removed and the wet weight determined. A small section of one horn is submitted for histology and the remainder used to isolate total RNA in order to evaluate complement component 3 gene expression.

EXAMPLE 60 6-Week Ovariectomized Rat Test Procedure—Bone and Cardioprotection

Female Sprague Dawley CD rats, ovx or sham ovx, are obtained 1 day after surgery from Taconic Farm (weight range 240-275g). They are housed 3 or 4 rats/cage in a room on a 12/12 (light/dark) schedule and provided with food (Purina 5K96C rat chow) and water ad libitum. Treatment for all studies begin 1 day after the animals arrival and dosed 7 days per week as indicated for 6 weeks. A group of age matched sham operated rats not receiving any treatment serve as an intact, estrogen replete control group for each study.

All treatments are prepared in 1% tween 80 in normal saline at defined concentrations so that the treatment volume is 0.1 mL/100g body weight. 17β-estradiol is dissolved in corn oil (20 μg/mL) and delivered subcutaneously, 0.1 mL/rat. All dosages are adjusted at three week intervals according to group mean body weight measurements.

Five weeks after the initiation of treatment and one week prior to the termination of the study, each rat is evaluated for bone mineral density (BMD). The total and trabecular density of the proximal tibia are evaluated in anesthetized rats using an XCT-960M (pQCT; Stratec Medizintechnik, Pforzheim, Germany). The measurements are performed as follows: Fifteen minutes prior to scanning, each rat is anesthetized with an intraperitoneal injection of 45 mg/kg ketamine, 8.5 mg/kg xylazine, and 1.5 mg/kg acepromazine.

The right hind limb is passed through a polycarbonate tube with a diameter of 25 mm and taped to an acrylic frame with the ankle joint at a 900 angle and the knee joint at 180°. The polycarbonate tube is affixed to a sliding platform that maintains it perpendicular to the aperture of the pQCT. The platform is adjusted so that the distal end of the femur and the proximal end of the tibia would be in the scanning field. A two dimensional scout view is run for a length of 10 mm and a line resolution of 0.2 mm. After the scout view is displayed on the monitor, the proximal end of the tibia is located. The pQCT scan is initiated 3.4 mm distal from this point. The pQCT scan is 1 mm thick, has a voxel (three dimensional pixel) size of 0.140 mm, and consists of 145 projections through the slice.

After the pQCT scan is completed, the image is displayed on the monitor. A region of interest including the tibia but excluding the fibula is outlined. The soft tissue is automatically removed using an iterative algorithm. The density of the remaining bone (total density) is reported in mg/cm³. The outer 55% of the bone is peeled away in a concentric spiral. The density of the remaining bone (Trabecular density) is reported in mg/cm³. One week after BMD evaluation the rats are euthanized by carbon dioxide suffocation and blood collected for cholesterol determination. The uteri are removed and the weights taken. Total cholesterol is determined using a Boehringer-Mannheim Hitachi 911 clinical analyzer using the Cholesterol/HP kit. Statitstics were compared using one-way analysis of variance with Dunnet's test.

EXAMPLE 61 MCF-7/ERE Antiproliferative Test Procedure

Stock solutions of test compounds (usually 0.1 M) are prepared in DMSO and then diluted 10 to 100-fold with DMSO to make working solutions of 1 or 10 mM. The DMSO stocks are stored at either 4° C. (0.1 M) or −20° C. (<0.1M). MCF-7 cells are passaged twice a week with growth medium [D-MEM/F-12 medium containing 10% (v/v) heat-inactivated fetal bovine serum, 1% (v/v) Penicillin-Streptomycin, and 2 mM glutaMax-1]. The cells are maintained in vented flasks at 37° C. inside a 5% CO₂/95% humidified air incubator. One day prior to treatment, the cells are plated with growth medium at 25,000/well into 96 well plates and incubated at 37° C. overnight.

The cells are infected for 2 hr at 37° C. with 50 μl/well of a 1:10 dilution of adenovirus 5-ERE-tk-luciferase in experimental medium [phenol red-free D-MEM/F-12 medium containing 10% (v/v) heat-inactived charcoal-stripped fetal bovine serum, 1% (v/v) Penicillin-Streptomycin, 2 mM glutaMax-1, 1 mM sodium pyruvate]. The wells are then washed once with 150 μλ of experimental medium. Finally, the cells are treated for 24 hr at 37° C. in replicates of 8 wells/treatment with 150 μλ/well of vehicle (<0.1% v/v DMSO) or compound that is diluted >1000-fold into experimental medium.

Initial screening of test compounds is done at a single dose of 1 μM that is tested alone (agonist mode) or in combination with 0.1 nM 17β-estradiol (EC₈₀; antagonist mode). Each 96 well plate also includes a vehicle control group (0.1% v/v DMSO) and an agonist control group (either 0.1 or 1 nM 17β-estradiol). Dose-response experiments are performed in either the agonist and/or antagonist modes on active compounds in log increases from 10⁻¹⁴ to 10⁻⁵ M. From these dose-response curves, EC₅₀ and IC₅₀ values, respectively, are generated. The final well in each treatment group contains 5 μl of 3×10⁻⁵ M ICI-182,780 (10⁻⁶ M final concentration) as an ER antagonist control.

After treatment, the cells are lysed on a shaker for 15 min with 25 μl/well of 1× cell culture lysis reagent (Promega Corporation). The cell lysates (20 μl) are transferred to a 96 well luminometer plate, and luciferase activity is measured in a MicroLumat LB 96 P luminometer (EG & G Berthold) using 100 μl/well of luciferase substrate (Promega Corporation). Prior to the injection of substrate, a 1 second background measurement is made for each well. Following the injection of substrate, luciferase activity is measured for 10 seconds after a 1 second delay. The data are transferred from the luminometer to a Macintosh personal computer and analyzed using the JMP software (SAS Institute); this program subtracts the background reading from the luciferase measurement for each well and then determines the mean and standard deviation of each treatment.

The luciferase data are transformed by logarithms, and the Huber M-estimator is used to down-weight the outlying transformed observations. The JMP software is used to analyze the transformed and weighted data for one-way ANOVA (Dunnett's test). The compound treatments are compared to the vehicle control results in the agonist mode, or the positive agonist control results (0.1 nM 15β-estradiol) in the antagonist mode. For the initial single dose experiment, if the compound treatment results are significantly different from the appropriate control (p<0.05), then the results are reported as the percent relative to the 15β-estradiol control [i.e., ((compound-vehicle control)/(17β-estradiol control-vehicle control))×100]. The JMP software is also used to determine the EC₅₀ and/or IC₅₀ values from the non-linear dose-response curves.

EXAMPLE 62 Inhibition of LDL Oxidation—Antioxidant Activity

Porcine aortas are obtained from an abattoir, washed, transported in chilled PBS, and aortic endothelial cells are harvested. To harvest the cells, the intercostal vessels of the aorta are tied off and one end of the aorta clamped. Fresh, sterile filtered, 0.2% collagenase (Sigma Type I) is placed in the vessel and the other end of the vessel then clamped to form a closed system. The aorta is incubated at 37° C. for 15-20 minutes, after which the collagenase solution is collected and centrifuged for 5 minutes at 2000×g. Each pellet is suspended in 7 mL of endothelial cell culture medium consisting of phenol red free DMEM/Ham's F12 media supplemented with charcoal stripped FBS (5%), NuSerum (5%), L-glutamine (4 mM), penicillin-streptomycin (1000 U/ml, 100 μg/ml) and gentimicin (75 μg/ml), seeded in 100 mm petri dish and incubated at 37° C. in 5%CO₂. After 20 minutes, the cells are rinsed with PBS and fresh medium added, this was repeated again at 24 hours. The cells are confluent after approximately 1 week. The endothelial cells are routinely fed twice a week and, when confluent, trypsinized and seeded at a 1:7 ratio. Cell mediated oxidation of 12.5 μg/mL LDL is allowed to proceed in the presence of the compound to be evaluated (5 μM) for 4 hours at 37° C. Results are expressed as the percent inhibition of the oxidative process as measured by the TBARS (thiobarbituric acid reactive substances) method for analysis of free aldehydes (Yagi K., Biochem Med 15:212-216 (1976)).

EXAMPLE 63 D12 Hypothalmic Cell Test Procedure

D12 rat hypothalamic cells are subcloned from the RCF17 parental cell line and stored frozen. They are routinely grown in DMEM:F12 (1:1), glutaMAX-1 (2 mM), penicillin (100 U/ml)-streptomycin (100 mg/ml), plus 10% fetal bovine serum (FBS). The cells are plated in phenol red-free medium (DMEM:F12, glutaMAX, penicillin-streptomycin) containing 2-10% charcoal stripped FBS at a subconfluent density (1-4×10 6 cells/150 mm dish). The cells are refed 24 h later with medium containing 2% stripped serum. To test for agonist activity, cells are treated with 10 nM 17β-estradiol or various doses of test compound (1 mM or a range from 1 pM to 1 mM). To test for antagonist activity the cells are treated with 0.1 nM 17β-estradiol in the absence or presence of varying doses (100 pM to 1 mM) of test compound. Control dishes are also treated with DMSO as a negative control. Forty-eight hours after hormone addition, the cells are lysed and binding test procedure performed.

For each binding test procedure 100-150 mg protein is incubated with 10 nM ³H-R5020+100-fold excess R5020 in a 150 ml volume. Triplicate reactions (three with R5020, three without R5020) are prepared in a 96 well plate. The protein extract is added first followed by ³H-R5020 or ³H-R5020+100× unlabeled R5020. The reaction is performed for 1-2 hr at room temperature . The reaction is stopped by the addition of 100 ml cold 5% charcoal (Norit SX-4), 0.5% dextran 69K (Pharmacia) in TE pH 7.4. After 5 min at room temperature, the bound and unbound ligand are separated by centrifugation (5 min, 1000 RCF, 4° C.). The supernatant solution (˜150 ml) is removed and transferred to a scintillation vial. Following the addition of scintillation fluid (Beckman Ready Protein+), the samples are counted for 1 min in a scintillation counter.

EXAMPLE 64 Progesterone Receptor in the CNS Preoptic Area

Sixty (60) day old female Sprague-Dawley rats are ovariectomized. The animals are housed in an animal care facility with a 12-h light, 12-h dark photoperiod and free access to tap water and rodent chow.

Ovariectomized animals are randomly divided into groups that are injected with vehicle (50% DMSO, 40% PBS, 10% ethanol vehicle), 15β-estradiol (200 ng/kg) or the compound to be tested. Additional animals are injected with the test compound 1 hr prior to injection of 15β-estradiol to evaluate the antagonistic properties of this compound. Six hrs after s.c. injection, animals are euthanized with a lethal dose of CO₂ and their brains collected and frozen.

Tissue collected from animals is cut on a cryostat at −16° C. and collected on Silane-coated microscope slides. The section-mounted slides are then dried on a slide warmer maintained at 42° C. and stored in desiccated slide boxes at −80° C. Prior to processing, the desiccated slide boxes are slowly warmed to room temperature (−20° C. for 12-16 hrs; 4° C. for 2 hrs; room temperature for 1 hr) to eliminate condensation formation on slides and thus minimize tissue and RNA degradation. The dry slides are loaded into metal racks, postfixed in 4% paraformaldehyde (pH 9.0) for 5 min and processed as previously described.

A plasmid containing a 815 bp fragment of the rat PR cDNA 9 (ligand binding domain) is linearized and used to generate a S35-UTP labeled probe that is complimentary to a portion of the rat PR mRNA. Processed section-mounted slides are hybridized with 20 μml of hybridization mix containing the riboprobe (4-6×10 6 DPM/slide) and 50% formamide and incubated overnight in a 55° C. humidified chamber. In the morning, the slides are placed in metal racks that are immersed in 2×SSC (0.15M NaCl, 0.015M sodium citrate; pH 7.0)/10 mM DTT. The racks are all transferred to a large container and washed in 2×SSC/10 mM DTT for 15 min at RT with gentle agitation. Slides are then washed in RNase buffer at 37° C. for 30 min, treated with RNase A (2 mg/ml) for 30 min at 37° C., and washed for 15 min in room temperature 1× SSC. Subsequently, the slides are washed (2×30 min) in 65° C. in 0.1×SSC to remove nonspecific label, rinsed in room temperature 0.1×SSC for 15 min and dehydrated with a graded series of alcohol: ammonium acetate (70%, 95%, and 100%). Air dried slides are opposed to x-ray film for 3 days and then photographically processed. The slides from all animals are hybridized, washed, exposed and photographically processed together to eliminate differences due to interassay variation in conditions.

EXAMPLE 65 Rat Hot Flush—CNS Effects

Ovariectomized-female, 60 day-old Sprague-Dawley rats are obtained following surgery. The surgeries are done a minimum of 8 days prior to the first treatment. The animals are housed individually under 12 h light/dark cycle and given standard rat chow and water ad libitum.

Two control groups are included in every study. Doses are prepared based on mg/kg mean group body weight in either 10% DMSO in sesame oil (sc studies) or in 1.0% tween 80 in saline (po studies). Animals are administered test compounds at doses ranging from 0.01 to 10 mg/kg mean group body weight. Vehicle and ethinyl estradiol (EE) controls (0.1 mg/kg, sc or 0.3 mg/kg, po) control groups are included in each test. When the compounds are tested for their antagonist activity, EE is coadministered at 0.1 or 0.3 mg/kg for sc or po studies, respectively. The test compounds are administered up to the day tail skin temperature is measured.

After the acclimation period of four days, the animals are treated once daily with the compound(s) of interest. There are 10 animals/treatment group. Administration of the compound is either by sc injection of 0.1 ml in the nape of the neck or po in a volume of 0.5 ml. On the 3rd day of treatment, a morphine pellet (75 mg morphine sulfate) is implanted subcutaneously. On the 5th day of treatment, one or two additional morphine pellets are implanted. On the eighth day, approximately half of the animals are injected with Ketamine (80 mg/kg, intramuscularly) and a thermocouple, connected with to a MacLab Data Acquisition System (API Insturments, Milford, Mass.) is taped on the tail approximately one inch from the root of the tail. This system allowed the continuous measurement of tail skin temperature. Baseline temperature is measured for 15 min, then naloxone (1.0 mg/kg) is given sc (0.2 ml) to block the effect of morphine and tail skin temperature is measured for one hour thereafter. On the ninth day, the remaining of the animals are set up and analyzed similarly.

EXAMPLE 66 Vasomotor Function in Isolated Rat Aortic Rings

Sprage-Dawley rats (240-260grams) are divided into 4groups:

-   1. Normal non-ovariectomized (intact) -   2. Ovariectomized (ovex) vehicle treated -   3. Ovariectomized 17β-estradiol treated (1 mg/kg/day) -   4. Ovariectomized animals treated with test compound (i.e., 1     mg/kg/day)

Animals are ovariectomized approximately 3 weeks prior to treatment. Each animal receives 1 mg/kg/day of either 17β-estradiol sulfate or test compound suspended in distilled, deionized water with 1% tween-80 by gastric gavage. Vehicle treated animals received an appropriate volume of the vehicle used in the drug treated groups.

Animals are euthanized by CO₂ inhalation and exsanguination. Their thoracic aortas are rapidly removed and placed in 37° C. physiological solution with the following composition (mM): NaCl (54.7), KCl (5.0), NaHCO₃ (25.0), MgCl₂2H₂O (2.5), D-glucose (11.8) and CaCl₂ (0.2) gassed with CO₂—O₂, 95%/5% for a final pH of 7.4. The advantitia is removed from the outer surface and the vessel is cut into 2-3 mm wide rings. Rings are suspended in at 10 mL tissue bath with one end attached to the bottom of the bath and the other to a force transducer. A resting tension of 1gram is placed on the rings. Rings are equilibrated for 1 hour, signals are acquired and analyzed.

After equilibration, the rings are exposed to increasing concentrations of phenylephrine (10⁻⁸ to 10⁻⁴ M) and the tension recorded. Baths are then rinsed 3 times with fresh buffer. After washout, 200 mM L-NAME is added to the tissue bath and equilibrated for 30 minutes. The phenylephrine concentration response curve is then repeated.

EXAMPLE 67 Eight Arm Radial Arm Maze—Cognition Enhancement

Male Sprague-Dawley, CD rats (Charles River, Kingston, N.Y.) weighing 200-250g on arrival are used. For one week, the rats are housed, six per cage, with standard laboratory chow and water available ad libitum. Housing is in a colony room maintained at 22° C. and had a 12 hour light/dark cycle with lights on at 6:00 AM. Following habituation to the facility, animals are individually housed and maintained at 85% of free-feeding weight. Once stable weights are attained, the rats are acclimated to the 8-arm radial maze.

The structure of the maze is an adaptation from that of Peele and Baron (Pharmacology, Biochemistry, and Behavior, 29:143-150, 1988). The maze is elevated to a height of 75.5 cm and composed of a circular area surrounded by 8 arms radiating away from the center, equidistant from one another. Each arm is 58 cm long×13 cm high. A clear plexiglass cylinder is loared to enclose the animal in the center portion of the maze prior to the start of each session. Each arm of the maze is equipped with 3 sets of photocells interfaced to a data acquisition unit, which in turn is interfaced to a computer. The photocells are used to track the movement of the rat in the maze. Pellet feeders located above food cups at the end of each arm, dispensed two 45 mg chocolate pellets when the outer photocell of the arm is activated for the first time in a given session. The maze is located in a testing room with black and white geometric posters on each wall to serve as visual cues. During all training and testing procedures, white noise is audible (˜70 db).

The training procedure consists of five phases, each with daily sessions lasting 5 or 10 minutes. A 10 second delay is imposed between the time the rat is placed in the center portion of the maze and when the cylinder is raised to begin the session. During Phase 1, food-restricted pairs of rats are placed on the maze for 10 minutes with 45 mg chocolate food pellets scattered throughout the 8 arms of the maze. During Phase II, each rat is placed individually on the maze for a 10 minute period, with pellets scattered from the middle photocell to the food cup of each arm. During Phase III, each rat is placed on the maze for a 10 minute period, with food pellets located only in and around the food cups in each arm. In Phase IV, each rat is allowed 10 minutes to collect two pellets from each arm. Re-entry into an arm is considered an error. Rats are trained daily in this manner until they achieved criterion performance with less than or equal to 2 total errors on three consecutive days of training. Total habituation and training time is approximately 3 weeks.

Test compound is prepared in phosphate buffered saline and administered in a volume of 1 ml/kg. Scopolamine HBr (0.3 mg/kg s.c.) served as the impairing agent, producing an increase in error rate (loss of memory). Test compound is given intraperitoneally simultaneously with scopolamine, 30 minutes prior to the first maze exposure on any given test day.

To assess the test compound, an 8×8 balanced latin square for repeated measures is designed, in order to achieve a high experimental efficiency with the least amount of animals. Eight experimental sessions, two per week, are conducted with the 8 treatments (vehicle, scopolamine, 3 doses of test compound in combination with scopolamine) randomized within each session. Each treatment followed every other treatment the same number of times. Therefore, the residual effect of every treatment could be estimated and removed from the direct treatment effect. Following ANOVA, multiple comparisons are performed using Dunnett's two-sided test on adjusted means.

Animals that did not make 4 correct choices within 5 minutes during the first exposure, or that had not made a total of 8 choices by the end of the 2nd exposure, are considered to have “timed-out” for that session. Any animal that “timed-out” following administration of more than one dose of the test compound is excluded from the analysis.

EXAMPLE 68 Neuroprotection Inhibition of Time-Dependent Death of Cells in Primary Cortical Neuron Cultures

Primary cortical neurons were produced from rat brains that were 0-1 day old using a variation of methods described by Monyer et al. 1989, Brain Research 483:347-354. Dispersed brain tissue was grown in DMEM/10% PDHS (pregnant donor horse serum) for three days and then treated with cytosine arabinoside (ARC) for two days to remove contaminating glial cells. On day 5, the ARC media was removed and replaced with DMEM/10% PDHS. The neuronal cells were cultured for a further 4-7 days before use.

Control primary neuronal cultures show progressive cell death between days 12 and 18 in culture. Twelve cultures were evaluated on days 12 and 16 for levels of the enzyme lactate dehydrogenase (LD) after adding test compound to 6 cultures maintained in DMEM and 10% PDHS on day 9 and maintaining the remaining cultures as controls. LD was assayed using a variation of the method by Wroblewski et al. 1955, Proc. Soc. Exp. Biol. Med. 90:210-213. LD is a cytosolic enzyme which is commonly used in both clinical and basic research to determine tissue viability. An increase in media LD is directly related to cell death.

Neuroprotection Against Cytotoxicity Induced by Hypoglycemia

C6glioma cells obtained from ATCC were plated in RPMI media with FBS at a concentration of 1×10<6>cells/ml in FALCON 25 cm² tissue culture flasks. Four hours prior to the onset of hypoglycemia, the maintenance media was discarded, monolayers were washed twice in the appropriate media and then incubated for four hours at 37° C. in either serum free or serum free plus test compound. Kreb's Ringer Phosphate buffer was used to wash the monolayers twice before the addition of appropriate glucose treatment. RPMI medium contains 2 mg glucose/ml; flasks were divided into groups of 6 each receiving 100% glucose (2 mg/ml), 80% glucose (1.6 mg/ml), 60% glucose (1.2 mg/ml) or 0% glucose (buffer) or supplemented with test compound. All flasks were incubated for 20 hours and then evaluated for total, live, and dead cell number utilizing trypan blue.

Neuroprotection Against Excitotoxic Amino Acids

Five culture dishes containing SK-N-SH neuroblastoma cells were treated with test compound and 5 culture dishes were treated with RPMI media. Four hours later, all cell were treated with NMDA (500 mu M) for 5 minutes. Total live cells and dead cells were then determined.

Neuroprotection Against Oxygen-Glucose Deprivation

Analysis of pyknotic nuclei to measure apoptosis: Cortical neurons are prepared from E18 rat fetus and plated in 8-well chamber slides precoated with poly-D-lysine (10 ng/ml) and serum at a density of 100,000 cells/well. Cells are plated in high glucose DMEM containing 10% FCS and kept in the incubator at 37° C. with 10% CO₂/90% air. On the next day, serum is removed by replacing culture media with high glucose DMEM containing B27 supplement and cells are kept in the incubator without further media change until the day of experiment. On day 6, slides are divided into two groups; control group and OGD group. Cells in control group receive DMEM with glucose and custom B27 (without antioxidants). Cells in OGD group receive no-glucose DMEM with custom B27, which has been degassed under vacuum for 15 min. Cells are flushed with 90% N₂/10% CO₂ for 10 min in an airtight chamber and incubated at 37° C. for 6 hrs. After 6 hrs, both control and OGD cells are subject to replacement of media containing either vehicle (DMSO) or test compound in glucose-containing DMEM with custom B27. Cells are returned to normoxic incubator at 37° C. After 24 hrs, cells are fixed in 4% PFA for 10 min at 4° C. and stained with Topro (Fluorescent nuclear binding dye). Apoptosis is assessed using Laser Scanning Cytometer by measuring pyknotic nuclei.

Measurement of LDH release as an indication of cell death: Cortical neurons are prepared from E18 rat fetus and plated in 48-well culture plates precoated with poly-D-lysine (10 ng/ml) and serum at a density of 150,000 cells/well. Cells are plated in high glucose DMEM containing 10% FCS and kept in the incubator at 37° C. with 10% CO₂/90% air. On the next day, serum is removed by replacing culture media with high glucose DDMM containing B27 supplement. On day 6, cells are divided into two groups; control group and OGD group. Cells in control group receive DMEM with glucose and custom B27 (without antioxidants). Cells in OGD group receive no-glucose DMEM with custom B27, which has been degassed under vacuum for 15 min. Cells are flushed with 90% N₂/10% CO₂ for 10 min in an airtight chamber and incubated at 37° C. for 6 hrs. After 6 hrs, both control and OGD cells are subject to replacement of media containing either vehicle (DMSO) or test compound in glucose-containing DMEM with custom B27. Cells are returned to normoxic incubator at 37° C. After 24 hrs, cell death is assessed by measuring cellular release of LDH (lactate dehydrogenase) into the culture medium. For LDH assay, an aliquot of 50 μl culture medium is transferred into the 96 well plate. After the addition of 140 μl 0.1M potassium phosphate buffer (pH 7.5) and 100 μl 0.2 mg/ml NADH, the plate is let sit in the dark at room temperature for 20 min. The reaction is initiated by the addition of 10 μl of sodium pyruvate. The plate is read immediately at 340 nM in a Thermomax plate reader (Molecular Devices). The absorbance, an index of NADH concentration, is recorded every 6 seconds for 5 minutes and the slope indicating the rate of NADH disappearance is used to calculate LDH activity.

-   -   LDH Activity(U/ml)=(ΔA/min) (TCF)(20) (0.0833)/(0.78)         -   where: 0.0833=proportionality constant             -   0.78=instrument light path length (cm)

Example 69 HLA Rat Test Procedure—Crohn's Disease and Inflammatory Bowel Disorders

Male HLA-B27 rats are obtained from Taconic and provided unrestricted access to a food (PMI Lab diet 5001) and water. At the start of the study, rats are 22-26 weeks old.

Rats are dosed subcutaneously once per day for seven days with one of the formulations listed below. There are five rats in each group and the last dose is administered two hours before euthanasia.

-   -   vehicle (50% DMSO/50% Dulbecco's PBS)     -   17α-ethinyl-17β-estradiol (10 μg/kg)     -   test compound

Stool quality is observed daily and graded according to the following scale: Diarrhea=3; soft stool=2; normal stool=1. At the end of the test procedure, serum is collected and stored at −70° C. A section of colon is prepared for histological analysis and an additional segment is analyzed for myeloperoxidase activity.

The following method is used to measure myeloperoxidase activity. Colon tissue is harvested and flash frozen in liquid nitrogen. A representative sample of the entire colon is used to ensure consistency between samples. The tissue is stored at −80° C. until use. Next, the tissue is weighed (approximately 500 mg) and homogenized in 1:15 w/v of 5 mM H₂KPO₄ (pH₆) washing buffer. The tissue is spun down at 20,000×g in a Sorvall RC 5B centrifuge for 45 minutes at 2-8° C. Supernatant is then discarded. Tissue is resuspended and homogenized in 2.5 ml (1:5 w/v) of 50 mM H₂KPO₄ with 10 mM EDTA and 0.5% Hex Ammonium Bromide to help solubilize the intracellular MPO. Tissue is frozen in liquid Nitrogen, thawed in a 37° C.-water bath and sonicated for 15 seconds to ensure membrane lysis. This procedure is repeated 3 times. Samples are then kept on ice for 20 minutes and centrifuged at 12,000×g for 15 minutes at 2-8° C. The supernatant is analyzed following these steps.

The test mixture is prepared by adding 2.9 ml of 50 mM H₂KPO₄ with 0.167 O-Dianisidine/ml with 0.0005% H₂O₂ into a reaction tube. When hydrogen peroxide is degraded, O-Dianisidine is oxidized and absorbs at 460 nm in a concentration dependent manner. The mixture is heated to 25° C. One hundred (100) μL of the tissue supernatant is added to the reaction tube, incubated for one minute at 25° C., then 1 ml is transferred to a disposable plastic cuvette. OD is measured every 2 minutes reaction time at 460 nm against a blank containing 2.9 ml of the reaction mixture and 100 μl of the 0.5% ammonium bromide solution.

Enzyme activity units are quantified by comparison of absorbence @ 460 to a standard curve prepared with purified human MPO 31.1 Units/Vial. The MPO is reconstituted and serially diluted using 50 mM H₂KPO₄ with 10 mM EDTA and 0.5% Hex Ammonium Bromide to four known concentrations. Sample absorbencies are compared against this curve to determine activity.

Histological analysis is performed as follows. Colonic tissue is immersed in 10% neutral buffered formalin. Each specimen of colon is separated into four samples for evaluation. The formalin-fixed tissues are processed in a vacuum infiltration processor for paraffin embedding. The samples are sectioned at 5 μm and then stained with hematoxylin and eosin (H&E) for blinded histologic evaluations using a scale modified after Boughton-Smith. After the scores are completed the samples are unblinded, and data are tabulated and analyzed by ANOVA linear modeling with multiple mean comparisons.

All patents, publications, and other documents cited herein are hereby incorporated by reference in their entirety. 

1. A compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 2. The compound of claim 1 wherein R⁸ is H.
 3. The compound of claim 2 wherein: R¹ and R² are each, independently, H, halogen, CN, phenyl, or lower alkyl, said phenyl and lower alkyl being unsubstituted; and R³, R⁴, R⁵, and R⁶, are each, independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy.
 4. The compound of claim 2 wherein the compound is of the formula:


5. The compound of claim 4 wherein R³, R⁵, and R⁶ are each independently H, Cl, F, methyl, or methoxy and R² is H, Cl, F, or methyl.
 6. The compound of claim 2 wherein the compound is of the formula:


7. The compound of claim 6 wherein R³, R⁵, and R⁶ are each independently H, Cl, F, methyl, or methoxy and R² is H, Cl, F, or methyl.
 8. The compound of claim 2 that is: (a) 4′-Hydroxy-3-methyl[1,1′-biphenyl]-4-carbaldehyde oxime; (b) 4′-Hydroxy[1,1′-biphenyl]-4-carbaldehyde oxime; (c) 3-Chloro-4′-hydroxy[1,1′-biphenyl]-4-carbaldehyde oxime; (d) 2-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (e) 3-Fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (f) 2-Chloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (g) 3-Chloro-4′-hydroxy-2′-methyl-1,1′-biphenyl-4-carbaldehyde oxime; (h) 4′-Hydroxy-2-methyl-1,1′-biphenyl-4-carbaldehyde oxime; (i) 3-Chloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (j) 3-Chloro-3′,5′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (k) 3,5-Dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (l) 3,5-Dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; (m) 2,3-Dichloro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime; or (n) 2,3-Dichloro-3′-fluoro-4′-hydroxy-1,1′-biphenyl-4-carbaldehyde oxime.
 9. A pharmaceutical composition comprising: a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof; and a pharmaceutical carrier.
 10. A compound of the formula

wherein: R¹ is OH or lower alkoxy; and R⁵, R⁶, and R⁷ are each, independently, H, OH, halogen, CN, phenyl, lower alkyl, lower alkoxy, said phenyl, lower alkyl, and lower alkoxy being optionally substituted; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 11. The compound of claim 10 wherein R⁵, R⁶, and R⁷ are each, independently, H, Me, Cl, F, or methoxy.
 12. The compound of claim 10 where the compound is 4′-Hydroxy-3-methoxy-1,1′-biphenyl-4-carbaldehyde oxime.
 13. A pharmaceutical composition comprising:

wherein: R¹ is OH or lower alkoxy; and R⁵, R⁶, and R⁷ are each, independently, H, OH, halogen, CN, phenyl, lower alkyl, lower alkoxy, said phenyl, lower alkyl, and lower alkoxy being optionally substituted; or a pharmaceutically acceptable salt thereof or a prodrug thereof; and a pharmaceutical carrier.
 14. A method of inhibiting osteoporosis in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

where R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 15. A method of inhibiting osteoarthritis, hypocalcemia, hypercalcemia, Paget's disease, osteomalacia, osteohalisteresis, multiple myeloma or other forms of cancer having deleterious effects on bone tissues in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 16. A method of inhibiting benign or malignant abnormal tissue growth in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 17. The method of claim 16 wherein the abnormal tissue growth is prostatic hypertrophy, uterine leiomyomas, breast cancer, endometriosis, endometrial cancer, polycystic ovary syndrome, endometrial polyps, benign breast disease, adenomyosis, ovarian cancer, melanoma, prostrate cancer, cancers of the colon, or CNS cancers.
 18. A method of lowering cholesterol, triglycerides, Lp(a), or LDL levels; or inhibiting hypercholesteremia; hyperlipidemia; cardiovascular disease; atherosclerosis; peripheral vascular disease; restenosis, or vasospasm; or inhibiting vascular wall damage from cellular events leading toward immune mediated vascular damage in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 19. A method of inhibiting free radical induced disease states in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 20. A method of providing cognition enhancement or neuroprotection; or treating or inhibiting senile dementias, Alzheimer's disease, congnitive decline, or neurodegenerative disorders in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 21. A method of inhibiting inflammatory bowel disease, ulcerative proctitis, Crohn's disease, colitis, hot flashes, vaginal or vulvar atrophy, atrophic vaginitis, vaginal dryness, pruritus, dyspareunia, dysuria, frequent urination, urinary incontinence, urinary tract infections, vasomotor symptoms; male pattern baldness; skin atrophy; acne; type II diabetes; dysfunctional uterine bleeding; or infertility in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof.
 22. A method of inhibiting leukemia, endometrial ablations, chronic renal or hepatic disease or coagulation diseases or disorders in a mammal in need thereof, comprising providing to said mammal an effective amount of a compound of the formula:

wherein R¹ and R², are each, independently, H, halogen, CN, phenyl, or lower alkyl; R³, R⁴, R⁵ and R⁶, are each independently, H, OH, halogen, CN, phenyl, lower alkyl, or lower alkoxy; R⁸ are each, independently, H, —C(O)R⁹, or lower alkyl; and R⁹ is lower alkyl; or a pharmaceutically acceptable salt thereof or a prodrug thereof. 